This is great, on the other hand what is the practical applicatio, like maybe clculate the growthrate of a bacteria or maybe charge cycle lengths of some accumulator, idk 😂
Quite complicated solution. What about: left side 8^(x-1)= (2^3)^(x-1)=2^3(x--1) This now to the base of two: log2^3.(x-1)=3(x-1).log2=3(x-1) [log 2 to the base of 2 = 1]] Right side log to the base of 2=log18 left side = right side => 3(x-1)=log18 => x = 1 + [log18]/3 = 2.389075...
Have more simple way is 8^x-1 = 2^3(x-1) = 2^3x-3 2^3x-3 = 18=2*9=2*3^2 divide by 2 both side 2^3x-3-1 = (2/2)(3^2) 2^3x-4 =3^2 log both side (3x-4)log2 = 2log3 divide log2 both side 3x-4 = 2(log3/log2) X= (2(log3/log2)+4)/3 Ans.
When I do 2 * log base 2 of 3 in a log calclator, I get 3.0978. So 4 + 3.0978 / 3 [all div by 3] = 7.0978/3 = 2.3659 . X = 2.3659. Then minus 1 gives 8 to 1.3659 = 17.121 NOT 18. So something is wrong!! You get to 1.389975 power. When I do log18/log8 I get 1.39. Whuch gives 18.0009
8^x×⅛=18 8^x=144 x=log144/log8=(4log2+2log3)/3log2=4/3+2log3/3log2 x≈4/3+(2×0.477)/(3×0.301)≈2158/903≈2.39 Deviation is about 0.0002 8^(2.39-1)≈18.0009
This is great, on the other hand what is the practical applicatio, like maybe clculate the growthrate of a bacteria or maybe charge cycle lengths of some accumulator, idk 😂
Quite complicated solution.
What about:
left side
8^(x-1)= (2^3)^(x-1)=2^3(x--1)
This now to the base of two:
log2^3.(x-1)=3(x-1).log2=3(x-1) [log 2 to the base of 2 = 1]]
Right side log to the base of 2=log18
left side = right side
=> 3(x-1)=log18
=> x = 1 + [log18]/3 = 2.389075...
Thank you for your solution, greatly appreciated perspective!
You're welcome! 👍
Have more simple way is 8^x-1 = 2^3(x-1) = 2^3x-3
2^3x-3 = 18=2*9=2*3^2 divide by 2 both side
2^3x-3-1 = (2/2)(3^2)
2^3x-4 =3^2
log both side
(3x-4)log2 = 2log3 divide log2 both side
3x-4 = 2(log3/log2)
X= (2(log3/log2)+4)/3 Ans.
Why not simply log of both sides?
(x-1) log8 = log18
x = 1 + log18/log8 = 2,389975
Test:
8^(2,389975-1) = 18
When I do 2 * log base 2 of 3 in a log calclator, I get 3.0978. So 4 + 3.0978 / 3 [all div by 3] = 7.0978/3 = 2.3659 . X = 2.3659. Then minus 1 gives 8 to 1.3659 = 17.121 NOT 18. So something is wrong!! You get to 1.389975 power. When I do log18/log8 I get 1.39. Whuch gives 18.0009
جميل❤
Shorter: log zur Basis2: (x-1) *3 ,= log (3^2*2) = 2log 3 +1 therefore
X = 1/3( 4+ 2 log 3)
👏
🙏♥️
I figured the answer out in my head within 5 seconds. This is crazy easy math, please try something challenging in the future.
How can u figure logs in your head?
The point of this is showing your work… how you came to that answer.
HOW do you get the answer > WHAT is X
What was your answer?
@davekearney1944 2.39 rounded off
The people throwing down decimals just didn't get it. Those are the same ones who are clueless when the battery dies.
X=2,39
Хоть мозги проветрил !!! Надо политиков проверять на такой херне , а то ведут нас на заклание !!!😢пусть лучше решения ищут😂😂😂
8^x×⅛=18
8^x=144
x=log144/log8=(4log2+2log3)/3log2=4/3+2log3/3log2
x≈4/3+(2×0.477)/(3×0.301)≈2158/903≈2.39
Deviation is about 0.0002
8^(2.39-1)≈18.0009
Let x-1 be equal to t,log 8^t=18, gives t log 8=18,so l log 18/log 8 =t,t=1.389975 implies x=1.389975+1=2.389975
Too easy to be in an Olympiad!
It depends on
x=1+ log18/log8
Log2^3 ifadesini yazarken once 3 sonra 2 yazmasi asiri sinir bozucu. Bu kadar kolay bir soruyu dakikalarca çözmeye ugrasmasi da öyle
My math is so rusty. I forget most everything. 2 + 2 = 5, correct?
😂👍
Çok saçma.bu kadar uzun çözüm mü olur.kim uydurmuş bu çözümü?sonra ne işe yarayacak?
😂
You have over complicated this...why?
Because he doesn't know much of anything else, so he spends all energy on this.
Und wozu braucht der normale Mensch das ?
All that just to say 18 = 18...
😂
But now try saying 19=19
Шашмалогия от класа!...
Too boring
It looks your IQ level is below average...Maybe you should play football :) :) :)
Typo: x = 2.389975...
That’s ridiculous no wonder I hated math