Great video. Btw, we could make the 1s proof simpler by skipping a few steps: if the sum of the internal angles of a triangle is 180 degrees, x+x+z+z= 180° 2x+2z=180° (dividing all by 2) x+z= 90°
2. Simpler: continue the radius through angle a. Then both angles (that compose angle a) are outside angles of left and right triangles, i.e. a = (w + w) + (y + y) = 2(w + y)
Please DO NOT Allow UA-cam to interrupt your carefully prepared videos with annoying pop-up ads. Those totally annoying interruptions utterly destroy the thought process.
Opposite angles in a cyclic quadrilateral add up to 180 degrees. I proved it like this (your way is much simpler): . Draw a circle and a cyclic quadrilateral ABCD, where A is opposite C and B is opposite D, inside it. . Label the angle 'a', which is angle DAB. . DAB is half of the angle at the origin subtending the same chord DB or arc DCB. Label the angle at the origin subtending chord DB '2a'. . Connect the origin to point C, bisecting angle DCB (opposite to DAB) with a radius. Now you have two isoceles triangles with the equal sides being radii. . Choose one isoceles triangle. The angle at the origin is bisected, so it's gone from 2a to a. a is opposite the base, so that means the other two angles are equal to each other. The angles in a triangle add up to 180 degrees. So each angle on the base of the triangle is (180-a)/2 degrees. One of those angles is the bisected angle DCB which is opposite to DAB. . (180-a)/2*2=180-a . (DCB=180-a)+(DAB=a)=180-a+a= 180 degrees. Opposite angles in a cyclic quadrilateral add up to 180 degrees.
Do you mean the opposite angles in a cyclic quadrilateral are supplementary? It's difficult to prove if the center of the circle is outside the quadrilateral. Maybe, the difficult cases are left out so that he can finish in time.
Sameer Sardana - some people need to see the interim steps and also he applied factorisation, doing an application one might not see straightaway. It’s just good and very enlightening to see the small steps.
I really appreciate all the help, I got 98 on my circle theorems exam. :)
good on you seman
Legit no one gives a flying fuck
When we talk about someone who not only knows his stuff but who also able to share what he knows.
Kaizer Chiefs fan eh?
Sundowns better
I’ve got my maths GCSE in a few hours. This really helped out, thanks.
Edit: I’m back, cos paper 2 is tmrw.
Edit 2: I’m sick of life
hah me too
Didnt come up
Riyadh Ul-Hoque might come up tomorrow
Me too
Mood
Your diagrammatic explanation super sir.. please do sir.,more videos about circle thereoms..
Thanks for the comment. Email me a list and i'll make the videos. Ninja is always willing to help students. onlinephysicsninja@gmail.com
@@PhysicsNinja no
@@joebastianich3410 seriously what was the point of this
Great video. Btw, we could make the 1s proof simpler by skipping a few steps:
if the sum of the internal angles of a triangle is 180 degrees,
x+x+z+z= 180°
2x+2z=180° (dividing all by 2)
x+z= 90°
Was just about to comment that
I thought of that too!
Thank you so much! You explain better than my teacher :’)))
Definitely
If a guy on youtube ( I know he's a tutor and all) is explaining your work better than your teacher, you may not have the best teacher.
@@honquewastaken2298 weird but true
I cannot explain how much this helped me, please more circle theorems
Ezio... you're learning geometry!?
2. Simpler: continue the radius through angle a. Then both angles (that compose angle a) are outside angles of left and right triangles, i.e. a = (w + w) + (y + y) = 2(w + y)
To all those tht watched this video 2 yrs (or more) ago , where r u in lyf rn??
Why the hell do you need to prove them in the first place?!
To understand it. In my school we only need to know the proofs, but learning this would make it much easier
Because in mathematics we need to prove that a statement actually works like it says. Just like a lawyer needs to prove someone is innocent.
I'm from south Africa and you just made me realize how interesting the circle theorems are (thank you)😭😭
I’ve got my maths mocks in a week and I’ve not understood this for months but this cleared everything up
Good luck!
did u pass
?
@@subhantariq3585 i got a 7 but was 1 mark off an 8
@@rileyhughes8530 noice
@@rileyhughes8530 lol one and a half years later you still replied. pretty coool
Maths gcse tuesday anyone?
Bingo
such a simple way of explaining proofs! they are almost not my nemesis anymore! just need to practice more tho
You really helped me, thank you!
awesome! keep up the good work
omagoddddddd :OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Please DO NOT Allow UA-cam to interrupt your carefully prepared videos with annoying pop-up ads. Those totally annoying interruptions utterly destroy the thought process.
do we have to show the previous proofs for the cyclic quadrilateral to proof it?
ik im one year late lol but you dont have to
I was worrying about circle but this video helped much
This is really helpful and clear in terms of proving where circle theorems are as such. Thank you so much for your video!
I write in 2 days. I think I get the basic idea of things but you really helped clarify better
Thanks so much, sir!!
Rally sad that this couldn't help me lol, my teacher does proofs in the weirdest way possible
Very useful video, but I would like to know how and through which apps u draw and write on the screen. Thanks.
I find it hard to follow the convoluted proofs I seem to find everywhere.
Then you come along with easy to understand proofs.
Thanks for doing this.
Much appreciated
😳Nice.....😵✌️🏳️🏳️🏳️
Thank you, this was really useful!
Imogen Owolade thanks!
Thanks so much I watched this video once and automatically understood everything
Thanx a lot you helped me .You are the best teacher definately please support him
Lil small child getting bored so watching this 😶
Great explanation and super writing on the whiteboard. What software are you using?
vivian laferla notability and a Wacom tablet
Watching videos about the properties of circles and triangles has become my new addiction.
My teacher is so lazy . She's not good ever ever
Good morning sir,
Thank you very much for these clear proofs. Steps are easy to follow and learn.
Very well explained and illustrated. Extremely useful. Kudos, good sir!
Honestly, You're amazing. I kid you not. Same video helped me twice. Thankyou sm.
Nice explanation really helped out
You make math seem easy and beautiful..
You’ll get there, took me 20 years. Thanks!
what are the factors that helped you prove the theorems?
This seriously helped me a lot
THANKS BRO
You just said what each angle is withou any proof or explanation
Hlo sir,
Actually you explain so well and i hv one request thai is can u explain about theorem of tangent in a circle ????
Let me look it up tonight and see what i can do to help.
Thanks bro .I'm Indian
Opposite angles in a cyclic quadrilateral add up to 180 degrees. I proved it like this (your way is much simpler):
. Draw a circle and a cyclic quadrilateral ABCD, where A is opposite C and B is opposite D, inside it.
. Label the angle 'a', which is angle DAB.
. DAB is half of the angle at the origin subtending the same chord DB or arc DCB. Label the angle at the origin subtending chord DB '2a'.
. Connect the origin to point C, bisecting angle DCB (opposite to DAB) with a radius. Now you have two isoceles triangles with the equal sides being radii.
. Choose one isoceles triangle. The angle at the origin is bisected, so it's gone from 2a to a. a is opposite the base, so that means the other two angles are equal to each other. The angles in a triangle add up to 180 degrees. So each angle on the base of the triangle is (180-a)/2 degrees. One of those angles is the bisected angle DCB which is opposite to DAB.
. (180-a)/2*2=180-a
. (DCB=180-a)+(DAB=a)=180-a+a= 180 degrees.
Opposite angles in a cyclic quadrilateral add up to 180 degrees.
so fucking helpful
It s super ! from France I discover your channel. very good pedagogy.
Excellent video. Thank you for sharing!
I liked this one! Would you also deduct a proof of so e of the double angle trig rules?
Really awesome explaination...u r efforts are commendable...
Physics ninja 😂
Love from India
also for question 4, how is it able to equal 2a?
Really helps with British GCSE'S
Cheers
Doing it tomorrow
Nice, simple and informative explanation
Ty I luv ur videos it amazing 👏 💓 💗 💖 💛 💕 👏 💓 😅😅😅😂😅🎉😅🎉
I love it 😍
Tomorrow 👀💔
Thanks man
if both angles in an isosceles triangle are 90 degrees. it wouldnt be a triangle anymore. idk
ASTAH KELIX KUDL MULUK MAR IN. LA MUZ DE KURFIN BALAN. ISD AHMU LAD KI PU ALINNSURAT. BURUT 'MATHEMATICS' US DO FELIX NA MURK HALL PIERSUM.
Thanks
thnku sir for giving me such a gd lecture:):)
the proof of the first theorem took some unnecessary steps: you don't need y and w...
damn you actually really good at explaining I love these videos
please make a video on trig functions
i would rlly help
and proofs
You did not explain why angle x = angle x (and angle z = angle z).
Really like how you teach and support students.
wow, this was easier than i thought it was
LOL watched this in class! Nice vid!
Hello comrade
This is a fantastic educational video
❤️✨
1. No need for y and w. Just x + (x+y) + y = 180 deg.
thanks so much this helped a ton!
This really helped!! ❤️😊
Which app or software did you use please?
Hello boi
thanks sir
this is reaally good thanks
THANKS MAN THAT WAS GREAT
HELP
Thx a lot , really helped me
Why not prove the second one before the first as it is just an application with angle 90... This would have saved you some time...
1/ Too complex. Its as simple as: 2x + 2z = 2(x+z) = 180. x+z = a = 90. No need for y nor w.
very helpful thanks
For question 3, I don't understand why must the angle c be able to = 2a?
For proof 3, why didn't you prove the angles on the other side of the segment are the same?
Do you mean the opposite angles in a cyclic quadrilateral are supplementary? It's difficult to prove if the center of the circle is outside the quadrilateral. Maybe, the difficult cases are left out so that he can finish in time.
What application are you using to make geometric figures?
@Dream sounds like this
This dude explained the stuff the teachers here take 5 weeks to understand
Thx so much!
But some proofs are not complete. The difficult cases are not included. You are in such a hurry. Why not give yourself more time?
Look at the title of the video
So he only had 10 minutes left!
This really helped me out thanks
subbed and liked
This is long yu really just need to say what theorem it’s is etc
*15mins
Velma Wall
1:14 freddy fazbear
Thank youuuu
Mocks tomorrow, you a champ
Crush it!
you could have taken 2x + 2z=180 directly from the large triangle. why so much work ?
Sameer Sardana - some people need to see the interim steps and also he applied factorisation, doing an application one might not see straightaway. It’s just good and very enlightening to see the small steps.
if 2 triangles which have angle angle angle similarity, who's points are the circle's edges, can they be proven congruent?
You can prove them congruent if they both have at least one equal or common corresponding side
New subscriber ❤️