would have been a good Jan 1st video, but it wasn't ready then - it's ready now! Join Wrath of Math to get exclusive videos, lecture notes, and more: ua-cam.com/channels/yEKvaxi8mt9FMc62MHcliw.htmljoin More math chats: ua-cam.com/play/PLztBpqftvzxXQDmPmSOwXSU9vOHgty1RO.html
it's my Mum's birthday this saturday, her 45th. While she's not nearly as interested in mathematics as I am, this is on the top of my list of things to tell her. We both really appreciate everyones congratulations. Thank you.
10:35 you used 8 twice instead of 9. It didn’t change the total, but I’m pretty sure the goal was to use each number 0-9 once. So 1^8 x 3^6 x 5^4 x 7^2 x 9^0
Thank you! I haven't watched anyone else's video on the topic, though maybe I should have. It's a balance between not wanting my presentation to be unduly or subconsciously influenced by someone else's, but also I hope my video does bring some unique explanations/facts/justifications/jokes. I assume if I just do my own thing without watching the others it will be unique in some way.
On the fact about adding 1 to every digit of 2025 being another perfect square 3136, it’s root, 56, is the result of adding 1 to each digit of 45, the root of 2025. Bad wording but ykwim
Perfect square years are going to become rarer The gap increses by 2 each time In the future, people wont be able to live to see even one perfect square year
@@shureee1 In Germany we celebrated the Lutherjahr, Göthejahr, and similar on the anniversaries of those historic people. Why not celebrating this event the whole year? It's a once-in-a-lifetime opportunity. 😏
It’s currently 11:43 p.m., so I zoned out for a moment while watching it. When I snapped back to reality, I just hear you go “so this graph is *actually* a tree!” I got the context, but it was super funny randomly lol. Thank you for putting so much thinking into this video! Very interesting.
Now I know why it’s called the spanning tree protocol. It is used in Ethernet networks to prevent messages from going in a loop and taking up all the bandwidth
Who knew 2025 could be so intriguing? Perfect squares, sums of cubes, and mathematical patterns make it fascinating. For me i have been using solutioninn too. It always helps me explore these topics. It is my secret weapon for breaking down complex math ideas like these.
2:25 Explaining that a product of any 2 numbers is equal to their average square squared minus their difference from being their average square squared. Formula: ab=((a+b)/2)²-(|a-b|/2)² Easy examples: 40*50=45²-5² 9*7=64-1 5*11=64-9 And in one case where this proof is harder to solve mentally than the above (but to show it works in a more generic form): 5*10=7.5²-2.5²=56.25-6.25
It’s kind of a coincidence. For any square, putting it into 2n+1 gets the next one. This incrementally increases the distance by 2, keeping it an odd number. It’s a coincidence that that’s how it worked out
3:45 Writing just has to be legible!! I can easily tell what ur writing. I hate how everything needs to be perfect cause I was always taught to be a perfectionist and I find it’s counterintuitive. Idk if ur handwriting is worse when u use a pen but I don’t think u need to worry about it
I love math videos like this one! Most people are unaware of the flaw in our numbering system that calls 1000 cubed a "billion" and 1000 to the 4th power "trillion", etc. This makes a decillion = 1000 to the 11th power, even though "dec" means 10, and so forth.
This year I become 20, and the sum of this number and the last 2 digits of this year (25) is 45, the square root of the year 2025. And, it's similar to these who become 25 this year, the sum of this number and the first 2 digits of this year (20) is 45, the square root of the year 2025.
4:55 That's only half of the people, who can say that! "People born in 1979 can say the same thing in 2025" up to their birthday, when they get 46. You've only considered people, who can say that after their birthday in 2025...
Edit 2: I have disliked all the comments that are from idiots who dont know what my comment means and dont make sense fun fact: 2024/4=506, often called the worst year in history HOW CAN I GET THIS _______ NUMBER WRONG I AM THE DUMBEST PERSON ON EARTH
5:22 Why start with 1^3 ? ----- you can start with 0^3. You can then say, "The sum of all the base 10 digits cubed is 2025." Of course you can do the same with the sum of all the digits squared.
You make the process of squaring numbers end in five more complicated than it is. You just multiply the the first one or two digits (the part in front of the five), by the next higher number and stick 25 to the back of the result.
i chose to present it in a way more akin to the general trick, 43^2 is easily found by "rounding up and down" giving 40*46 + 3^2 ; 78^2 by doing 76*80 + 2^2 ; etc.
@@WrathofMath While from the other angle, I found this proof solely from looking at the multiplication table. A few years later, my 9th grade teacher wanted me to submit a proof on it and through that experience could generalize it basically to the point shown in the video with rearranging elements.
My favorite UA-cam in history. Tech videos and DIY videos are my other loves, but math was that subject I excelled at in the number 1 spot in grade school. This excited me.
13:15 You don't have to calculate it that way! Assume, that all numbers are double digits and count 1+...+45 one way (1) and back (2), so you get 45 * 46. Reduce this by the single digit numbers sum (45) => 45 * (46 - 1) = 45 * 45 = 2025.
For all my American friends 3mi = 5km 5mi = 8km 8mi = 13km 13mi = 21km 21mi = 34km and so on And also , 3m = 5×2ft 5m = 5×3ft 8m = 5×5ft 13m = 5×8ft I through it was too golden to ignore in a math video like this one 😅
You can get any number sequence if you round enough... Just so happens for the first few numbers in the sequence only a minimal amount of rounding is required.
You might be right - I don't see mult tables in the wild much - but it would make sense to have a 9x9 table since that's as big as possible without 2 digit multiplication. Certainly less arbitrary than an 8x8 table anyways.
@@WrathofMath I think they have kids go to 12 because it’s the biggest they can reasonably be expected to remember. Or it’s left over from when English had way more base 12 influence (gross, etc)
That 40×50 + 5² is an application of difference of squares and how I calculate squares in my head if the need ever arises. The trick that makes it useful is when you choose the ±b in a way that leaves one of the factors with multiple trailing zeroes. For example, 381² = 400×362 + 19² = 144800 + 20×18 + 1² = 144800 + 360 +1 = 145161.
2025 is going to be complex ,odd and unhappy But ,wholly Real ,natural and composite of Abundant positiveness . believe in your self but don't be a Narcissist squarely.
On NYE, I noticed that 2025 was divisible by 25, which my mental math skills told me was 81x25, and I noticed the two squares immediately. Changed my name in an online game to 3x3x3x3x5x5=. Nobody got it so I put in 2025 after the equals. Only some people on a France server thought it was cool and I heard them checking the math.
If my teacher told me that one day you could use this knowledge from school and flex. Now we must wait another 91 year ... I think you have prepared for this for years ... Thanks you 😊
I love weird math coincidences and numbers that apply to many at once. Nine is my favorite number because it’s an example of a mathematical “fixed point” of our number system: if you take any number with two or more digits, subtract the sum of its digits, and iterate until you have a single digit number, that number will always be nine.
2025 is the Square of 45 and if you add 1 to every number it is the Square of 56 but if you only add 1 to the First number is 55, so you do the exakt same thing with the Square, you do with the root
Bravo! I think you included pretty much every cool fact I've come across about 2025 so far, with few exceptions, and I was wholly unprepared for the graph theory section but it all made sense at the end of it.. you are good like that. One thing Domotro from Combo Class noticed which I found amazing was that 2025 is an early element in the sequence generated by iterating as such: Where T(n) is a triangular number, and with n > 1: T(2) = 3 3^2 = 9 T(9) = 45 45^2 = 2,025 T(2,025) = 2,051,325 2,051,325^2 = 4,207,934,255,625 T(4,207,934,255,625) = 8,853,355,349,833,265,389,198,125 Tn^2 = 78,381,900,950,421,300,982,881,904,787,876,752,731,430,503,515,625 So then necessarily Where k = sum of first n cubes with n > 1 n = 2, k = 9 n = 9, k = 2,025 n = 2,025, k = 4,207,934,255,625 k = 78,381,900,950,421,300,982,881,904,787,876,752,731,430,503,515,625 I just thought that was worth sharing bc it's kinda neat. I love that the 2025th triangular number is 2051325... CUTE!❤
Good job explaining such difficult mathematical methods. I didn't understand most of it, but that's not your fault. Thanks for the video, it was certainly interesting.
14:09 you can do this in a funner way I think. Add another 1+2+3+...+9 and su tract 45. Then you have 2*(1+2+...+45)-45, which becomes 2*45*46/2-45=45*46-45=45*45
Fun fact: The first trick also works for 3025. (30 + 25)² = 3025 In fact, this trick only works for three possible pairs of positive integers. (20 + 25)² = 2025 (30 + 25)² = 3025 (98 + 01)² = 9801 (although this one feels a bit like cheating)
I hear you as to your number 5 issue. I consistently mess up the number 8. I mean it’s just 2 circles. I can smoothly write infinity, but not 8. Go math!💕🐝💕
Here’s a Fun Fact: You can easily tell if a number is divisible by 5 by looking at the last digit. If the last digit is either 5 or 0 then Conglaturations, your number is divisible by 5! (Yes I spelled congratulations wrong but I did it on purpose)
videos like these are so interesting that eventually I get captivated, don’t remember what video I was watching, click off and back on to youtube, then finally click my mind back this process repeats until I click off which I usually can’t. Oh and these facts are interesting too
There's a theory I know in squares. You get 2 variables, a and b. A = 45² = 2025 B = 46² = ? You get the square root of A, double it and add 1, then add it to A. So the square root of 2025 is 45, 45x2 = 90, 90+1 = 91, 2025+91 = 2116 = 46² = B. This is also true for 47
6:55 ALSO 20 is right next to 25 in the 9 multiplication table, directly in the center, I know it’s really just multiples of 5 but it’s fun to see that it’s literally right in the middle!
I was able to recreate the early ones in an Excel sheet for all posterity. But couldn't get a 2025 character number entered easily; probably could do some concatenation to force it. "An Excel cell can hold a maximum of 32,767 characters, with only 1,024 characters displayed and all 32,767 visible in the Formula bar." Note that 2025 = 2^10 + 1001, which is a formula using only the digits 0, 1, and 2.
This may be a variation of something you said, but: Add the digits of 2025: 2+0+2+5=9 Then multiply the digits (without the 0): 2*2*5=225 Finally, multiply these 2 numbers: 9*225=2025 Am I stretching it here?
As a person who doesn't enjoy mathematics at all, I have to say amazing video. I appreciate the insights and fun presented in your message. I can also say I think I dislike math even more because my brain hurts now... That was a workout... Thank you 🤪
And I was 45 when it turned 45² on january 1st. That's pretty neat! And here i was bummed that it was no longer 2024, because I think it's a pretty number, much prettier than 2025, but I'm starting to warm up to 2025.
It is the number of the year where we wished it were the end of humanity and/or the the world but when we were not fortunate enough to be put out of our misery.💥
would have been a good Jan 1st video, but it wasn't ready then - it's ready now!
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u write 2 as Ղ
i love it
Cant wait for 2027 because its a prime year
Fun fact: (5(2+0+2+5))²=2025
@@kupiner unfunny fact
it's my Mum's birthday this saturday, her 45th. While she's not nearly as interested in mathematics as I am, this is on the top of my list of things to tell her.
We both really appreciate everyones congratulations. Thank you.
Happy birthday to your mum!
Happy birthday huge gamer’s mom.
Happy birthday!
THAT'S SO RARE
Happy birthday to your mom 🥳
My dad is 45 and he’s a huge nerd. Can’t wait to tell him 😂
Congratulations 😂
Let us know his reaction! I'm curious
update?
my mum is 45 (until may 4 where she is 46 for a yr)
My mom will be 45 this October
10:35 you used 8 twice instead of 9. It didn’t change the total, but I’m pretty sure the goal was to use each number 0-9 once. So 1^8 x 3^6 x 5^4 x 7^2 x 9^0
I noticed that too. It's not a big deal tho.
@tameemkamal1 IT ANGERS ME SO MUCH I DONT KNOW HOW YOU CAN LIVE LIKE THAT
@tameemkamal1 sorry no hate was intended it just infuriates me
@@likuyt-__- he's not that into math i guess? thats why?
Sharp eye on the Sharpie, Brian Brain.
The first half of the video:
Cool facts about 2025
Second half:
Graph theory
I've seen a couple of other videos about 2025 being special, but yours is by far the best!
Thank you! I haven't watched anyone else's video on the topic, though maybe I should have. It's a balance between not wanting my presentation to be unduly or subconsciously influenced by someone else's, but also I hope my video does bring some unique explanations/facts/justifications/jokes. I assume if I just do my own thing without watching the others it will be unique in some way.
How did you comment 3 hrs ago??
absolute cinema
@@adrielwaderivera1974 it was a members first video, thats how
Perfect square
Matt Parker was been waiting for this for his entire life. December 22nd he’s gonna have a big party for his 45th birthday.
The question is, if he had been born 10 days later, would he have been as interested in maths?
Me born on 23rd december being 18 this year
@@LuigiCotocea 40% of the required age
@@abngmg I know but i have the date very close to him
On the fact about adding 1 to every digit of 2025 being another perfect square 3136, it’s root, 56, is the result of adding 1 to each digit of 45, the root of 2025. Bad wording but ykwim
ikwym
Wtf
very poetic that we’re getting the minecraft movie in a perfect square year!
here’s hoping the game still exists in 2197 🎉
cube year would be BETTER !
2116 actually
@@pandolphe1669 It's a sum of cubes year, and minecraft is filled with...
Mc will lose copyright in like 2111 because laws so...
What if.. it was a cube year? The closest cubed whole number year would be 2197, or 13³.
Perfect square years are going to become rarer
The gap increses by 2 each time
In the future, people wont be able to live to see even one perfect square year
glad i don't live at the same time as those losers!
quite a chunk of the people born in 2026 wont
And then in the 1st century, it happens 10 times
Life expectation might increase faster than the root of the year number.
It actually does currently, right?
@@WrathofMath "Longevity Escape Velocity" to the rescue !
If youre born in 1979 you can say that you were x years old at the start of year x²
but it’s a bit more lame since you don’t get the birthday
@@pe1900It's a whole year of celebration. 🤣
that year is when my dad is born
pov: you're born on Jan 1st
@@shureee1 In Germany we celebrated the Lutherjahr, Göthejahr, and similar on the anniversaries of those historic people. Why not celebrating this event the whole year? It's a once-in-a-lifetime opportunity. 😏
It’s currently 11:43 p.m., so I zoned out for a moment while watching it. When I snapped back to reality, I just hear you go “so this graph is *actually* a tree!” I got the context, but it was super funny randomly lol. Thank you for putting so much thinking into this video! Very interesting.
Now I know why it’s called the spanning tree protocol. It is used in Ethernet networks to prevent messages from going in a loop and taking up all the bandwidth
Who knew 2025 could be so intriguing? Perfect squares, sums of cubes, and mathematical patterns make it fascinating. For me i have been using solutioninn too. It always helps me explore these topics. It is my secret weapon for breaking down complex math ideas like these.
2:25 Explaining that a product of any 2 numbers is equal to their average square squared minus their difference from being their average square squared. Formula: ab=((a+b)/2)²-(|a-b|/2)²
Easy examples:
40*50=45²-5²
9*7=64-1
5*11=64-9
And in one case where this proof is harder to solve mentally than the above (but to show it works in a more generic form):
5*10=7.5²-2.5²=56.25-6.25
I came to the comments looking for this explanation. Thanks! More people need to give you a thumbs up.
Was looking for this comment and thanks
3:00
2025 = 45^2
+1111 +11
3136 = 56^2
Is this just coincidence or is there some series or something behind this?
It’s kind of a coincidence. For any square, putting it into 2n+1 gets the next one. This incrementally increases the distance by 2, keeping it an odd number. It’s a coincidence that that’s how it worked out
56² + 1353 = 67²
no pattern
the difference are f(x) = 11(22x - 9)
If you check 56²-45²=(56-45)(56+45)=11×101, you'd realize that all these happens only because 56 and 45 randomly sum up to 101
2025 = 45^2
+ 1000 +10
3025 = 55^2
I'll make sure to be around for year 22,325,625, and I was around for year 9.
Time to give up the booze, fags and base jumping. 😉
Fun Fact: 2025 is funnier than 2024
😭
3:45 Writing just has to be legible!! I can easily tell what ur writing. I hate how everything needs to be perfect cause I was always taught to be a perfectionist and I find it’s counterintuitive. Idk if ur handwriting is worse when u use a pen but I don’t think u need to worry about it
i've worked hard on improving my handwriting over the years, and I've made strides - but every now and again a really ugly number slips out!
I love math videos like this one! Most people are unaware of the flaw in our numbering system that calls 1000 cubed a "billion" and 1000 to the 4th power "trillion", etc. This makes a decillion = 1000 to the 11th power, even though "dec" means 10, and so forth.
2:00 i dont think ill live to be 107 years old
You have a shot!
yo same i would be 107 in 2116
16 year anniversary olds
91 + 11 = 102.
Yoo I have a shot!
I would need to be 106
This year I become 20, and the sum of this number and the last 2 digits of this year (25) is 45, the square root of the year 2025.
And, it's similar to these who become 25 this year, the sum of this number and the first 2 digits of this year (20) is 45, the square root of the year 2025.
6:22 A Gen Beta hearing this fact about the year they were born in:
“My birth year is special! To see why, we can use the Sigma function!”
🗿
wasn’t it “stigma” or is it actually “sigma”?
@@Only-Astro-sit’s sigma both in the meme and in the math (the sum symbol is the letter sigma)
24:18 that "and then 3 times 2 of course is 6" got me nodding along like ahh yes of course, I know this!
Happy new year! 2025 is a neat number!
At 10:36 wouldn't it be 9^0?
100% right. He was just unleashing his wrath, on math.
True.. luckily the zero exponent saves the final result.
Came here to comment the exact same thing! While it doesn't change anything, aesthetics have been broken!
lost the opportunity to end the video at 20:25
it's also divisible by 9 (2+0+2+5=9 (all numbers divisible by 9 will always add down to 9) 9x 225= 2025
Like that Beatles song 😉
4:55 That's only half of the people, who can say that!
"People born in 1979 can say the same thing in 2025" up to their birthday, when they get 46.
You've only considered people, who can say that after their birthday in 2025...
Edit 2: I have disliked all the comments that are from idiots who dont know what my comment means and dont make sense
fun fact: 2024/4=506, often called the worst year in history
HOW CAN I GET THIS _______ NUMBER WRONG I AM THE DUMBEST PERSON ON EARTH
its 536
@@blumaster Are you crazy?!
@@AavyanTiwarihomie isn't talking abt the math
i agree alot my dad complained alot about the year 2024
Why is it the worst year in history?
5:22
Why start with 1^3 ? ----- you can start with 0^3.
You can then say, "The sum of all the base 10 digits cubed is 2025."
Of course you can do the same with the sum of all the digits squared.
Odd Numbers: 13579
Even Numbers: 02468
18:35 So are we just not gonna talk about that freaky-ass highlighter tip?!
yes
its seethrough so you can see what your highlighting.
It's nice... What else is there to talk about?
@@WrathofMath I have waited 45 years to finally learn what in the heck a spanning tree is !
You make the process of squaring numbers end in five more complicated than it is. You just multiply the the first one or two digits (the part in front of the five), by the next higher number and stick 25 to the back of the result.
i chose to present it in a way more akin to the general trick, 43^2 is easily found by "rounding up and down" giving 40*46 + 3^2 ; 78^2 by doing 76*80 + 2^2 ; etc.
@@WrathofMath While from the other angle, I found this proof solely from looking at the multiplication table. A few years later, my 9th grade teacher wanted me to submit a proof on it and through that experience could generalize it basically to the point shown in the video with rearranging elements.
My favorite UA-cam in history. Tech videos and DIY videos are my other loves, but math was that subject I excelled at in the number 1 spot in grade school. This excited me.
Most people just drink alcohol. This guy just needs paper and a sharpie.
yup, and funnily enough i don't drink and never have
13:15 You don't have to calculate it that way! Assume, that all numbers are double digits and count 1+...+45 one way (1) and back (2), so you get 45 * 46. Reduce this by the single digit numbers sum (45) => 45 * (46 - 1) = 45 * 45 = 2025.
W Comment
Wonderful video. I love seeing these amazing math fun facts.
You just answered NPR’s Sunday puzzle! Arrange the numbers 2, 3, 4, and 5 using standard operations to get to 2025. 3^4 * 5^2. So cool!
ok that last one was a bit of a stretch but I loved the video
For all my American friends
3mi = 5km
5mi = 8km
8mi = 13km
13mi = 21km
21mi = 34km and so on
And also ,
3m = 5×2ft
5m = 5×3ft
8m = 5×5ft
13m = 5×8ft
I through it was too golden to ignore in a math video like this one 😅
FIBONACCI!!?????!!!!!!!
You can get any number sequence if you round enough... Just so happens for the first few numbers in the sequence only a minimal amount of rounding is required.
I don’t think I’ve ever seen a 9x9 multiplication table. It was always 12x12, or maybe sometimes 10x10.
You might be right - I don't see mult tables in the wild much - but it would make sense to have a 9x9 table since that's as big as possible without 2 digit multiplication. Certainly less arbitrary than an 8x8 table anyways.
@@WrathofMath I think they have kids go to 12 because it’s the biggest they can reasonably be expected to remember. Or it’s left over from when English had way more base 12 influence (gross, etc)
That 40×50 + 5² is an application of difference of squares and how I calculate squares in my head if the need ever arises. The trick that makes it useful is when you choose the ±b in a way that leaves one of the factors with multiple trailing zeroes. For example, 381² = 400×362 + 19² = 144800 + 20×18 + 1² = 144800 + 360 +1 = 145161.
2025 is going to be complex ,odd and unhappy But ,wholly Real ,natural and composite of Abundant positiveness . believe in your self but don't be a Narcissist squarely.
6:54 I've actually never seen a 9x9 multiplication table before now, only 10x10 and 12x12
9:50 this one is my favorite
On NYE, I noticed that 2025 was divisible by 25, which my mental math skills told me was 81x25, and I noticed the two squares immediately. Changed my name in an online game to 3x3x3x3x5x5=. Nobody got it so I put in 2025 after the equals. Only some people on a France server thought it was cool and I heard them checking the math.
Got to love an oblique reference to Edwin F. Beckenbach's famous paradox at the start!
Now I can rest easy knowing I get to live through a mathematical coincidence.
Ooh what a way to start off the new year
The first days are Wednesday, Thursday, and Friday, making WTF. What a way to start of the year.
20+25 = 45 which if put to the power of 2 equals 2025, reminds me of fractals
Average maths competition questions. Amazing and hilarious video!
(20+25)^2=2025
If my teacher told me that one day you could use this knowledge from school and flex. Now we must wait another 91 year ... I think you have prepared for this for years ...
Thanks you 😊
I love weird math coincidences and numbers that apply to many at once. Nine is my favorite number because it’s an example of a mathematical “fixed point” of our number system: if you take any number with two or more digits, subtract the sum of its digits, and iterate until you have a single digit number, that number will always be nine.
2025 is the Square of 45 and if you add 1 to every number it is the Square of 56 but if you only add 1 to the First number is 55, so you do the exakt same thing with the Square, you do with the root
Man, I love Mathematics.
Bravo! I think you included pretty much every cool fact I've come across about 2025 so far, with few exceptions, and I was wholly unprepared for the graph theory section but it all made sense at the end of it.. you are good like that.
One thing Domotro from Combo Class noticed which I found amazing was that 2025 is an early element in the sequence generated by iterating as such:
Where T(n) is a triangular number,
and with n > 1:
T(2) = 3
3^2 = 9
T(9) = 45
45^2 = 2,025
T(2,025) = 2,051,325
2,051,325^2 = 4,207,934,255,625
T(4,207,934,255,625) = 8,853,355,349,833,265,389,198,125
Tn^2 = 78,381,900,950,421,300,982,881,904,787,876,752,731,430,503,515,625
So then necessarily
Where k = sum of first n cubes with n > 1
n = 2, k = 9
n = 9, k = 2,025
n = 2,025, k = 4,207,934,255,625
k = 78,381,900,950,421,300,982,881,904,787,876,752,731,430,503,515,625
I just thought that was worth sharing bc it's kinda neat.
I love that the 2025th triangular number is 2051325... CUTE!❤
1936 started with WTF (wed, thurs, fri), 2025 also started with wtf
what the f 😮
You really snuck in a whole lesson on graph theory but pulled it together in the end.
I cant help myself
Good job explaining such difficult mathematical methods. I didn't understand most of it, but that's not your fault. Thanks for the video, it was certainly interesting.
14:09 you can do this in a funner way I think. Add another 1+2+3+...+9 and su tract 45. Then you have 2*(1+2+...+45)-45, which becomes 2*45*46/2-45=45*46-45=45*45
Or in general you get n(n+1)-45 which explains why you only get n^2 for n=45 and not for any other number n
Revenge of the Nerds, just too much. My head is hurting.
Really nice video!
Learned more math here than in all of high school, type of comments incoming. (Bless my math teachers were great)
Very cool video dude! Keep it up!
Thank you!
8:57 you can also add 1 to the power of 0
Yes weather of math. 2025 is indeed an odd number, good observation
thanks gerber
People born in 1979 can also be 45 in the year 45^2.
Fun fact:
The first trick also works for 3025.
(30 + 25)² = 3025
In fact, this trick only works for three possible pairs of positive integers.
(20 + 25)² = 2025
(30 + 25)² = 3025
(98 + 01)² = 9801 (although this one feels a bit like cheating)
I hear you as to your number 5 issue. I consistently mess up the number 8. I mean it’s just 2 circles. I can smoothly write infinity, but not 8. Go math!💕🐝💕
Great explanation of how to count the spanning trees of K_{3,n} !
Thank you!
10:55 weren't you supposed to write 9^0 (not 8^0) so base is odd?
yup! my bad
Yeah, but both equals 1
It is still equal to 22,325,625 if you wrote 9⁰
In the example starting at about 10:30, did you mean to put 1 to the power of 9, not 8? The 8 gets covered at the other end (8 ^ 0) 🙂
1^8 is correct, but it should be 9^0 (well, either would work, but this would be the way to keep on theme with odd bases and even indices)
I was thinking the same thing
Domotro from Combo Class picked up on this too!
Here’s a Fun Fact:
You can easily tell if a number is divisible by 5 by looking at the last digit. If the last digit is either 5 or 0 then Conglaturations, your number is divisible by 5! (Yes I spelled congratulations wrong but I did it on purpose)
It's really a once in a life time year to live in.
videos like these are so interesting that eventually I get captivated, don’t remember what video I was watching, click off and back on to youtube, then finally click my mind back
this process repeats until I click off which I usually can’t. Oh and these facts are interesting too
You have my subscription, good sir.
Interestingly, at the beginning of 2025 I’m still 25. So, in the year 45^2, I was 5^2 years old!
So “in the years y^x, I was z^x years old” if I’m correct
@@BangladeshTheBestyes, that is one way to put it 😊
I only gotta make it to 109. Thats a good excuse to get in better shape i guess. Along with that movie which will release in 2115.
3136 -> 56^2.
2025 -> 45^2
45, then add every digit with 1 -> 56
WHA-
Thanks for Greenneko8020 for pointing out the mistake!
45^2 = 2025
@greenneko8020 oh, thx for pointing it up (I mistyped :/)
There's a theory I know in squares.
You get 2 variables, a and b.
A = 45² = 2025
B = 46² = ?
You get the square root of A, double it and add 1, then add it to A.
So the square root of 2025 is 45, 45x2 = 90, 90+1 = 91, 2025+91 = 2116 = 46² = B.
This is also true for 47
6:22 sigma
6:55 ALSO 20 is right next to 25 in the 9 multiplication table, directly in the center, I know it’s really just multiples of 5 but it’s fun to see that it’s literally right in the middle!
I was able to recreate the early ones in an Excel sheet for all posterity. But couldn't get a 2025 character number entered easily; probably could do some concatenation to force it.
"An Excel cell can hold a maximum of 32,767 characters, with only 1,024 characters displayed and all 32,767 visible in the Formula bar." Note that 2025 = 2^10 + 1001, which is a formula using only the digits 0, 1, and 2.
Add the digits together, if it equals 9, then then it's divisible by bu 9 it say 90 = 9+0 it 99=9+9=18.18= 1+8
This may be a variation of something you said, but:
Add the digits of 2025: 2+0+2+5=9
Then multiply the digits (without the 0): 2*2*5=225
Finally, multiply these 2 numbers: 9*225=2025
Am I stretching it here?
Thanks, Chris Griffin!
1:29
Robert langlands (1936) : mathematician
Robert Schöeneberg (2013) : mathematician
oh my! I learned a lot in this video. Thank you so much, taught me more than my math lessons 100% haha. Anyways, im subscribing!!
Thank you!
As a person who doesn't enjoy mathematics at all, I have to say amazing video. I appreciate the insights and fun presented in your message. I can also say I think I dislike math even more because my brain hurts now... That was a workout... Thank you 🤪
It's good for you!
one time i was on a walk and i had the irresistable urge to check what is the next prime numbered year.
Happy new year!
And I was 45 when it turned 45² on january 1st. That's pretty neat! And here i was bummed that it was no longer 2024, because I think it's a pretty number, much prettier than 2025, but I'm starting to warm up to 2025.
7:00 i find this interesting, because i grew up always using a 12x12 times table
Man that was amazing!
Thank you!
It is the number of the year where we wished it were the end of humanity and/or the the world but when we were not fortunate enough to be put out of our misery.💥
Fun fact: evey square number besides multiples of five is one away from a multiple of five. This means no square number will have 3 4 7 or 8
14:23 Easier to see that it is equal to
2 *( sum of 1..45) - sum of 1..9 so
2*(45/2*(1+45)) - 45 or 45*(1+45)-45 leaving
45*45
Thanks, I never knew 2025 was odd.
Me neither!