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eroshea
Group Title
find all the critical point of f(x) = 3x^(5/3)  15x^(2/3)
 one year ago
 one year ago
eroshea Group Title
find all the critical point of f(x) = 3x^(5/3)  15x^(2/3)
 one year ago
 one year ago

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terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Critical points are points where the derivative is zero.
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Of course, differentiate first :)
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
ok.. i got x=0, x=2
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
let's see.... \[\Large \frac{d}{dx}\left(3x^{\frac53}15x^{\frac23}\right)=5x^{\frac23}10x^{\frac13}\]
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
is my answer correct?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Try 0. the derivative doesn't exist, because you have... \[\Large 5x^{\frac23}10x^{\frac13}=5x^{\frac23}\frac1{10x^{\frac13}}\] an x in the denmoinator.
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
so that will be disregarded right? so i will have 2 for the value of x
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
so yes, that is a critical point (sorry, I forgot to mention that points where the derivative does not exist are also critical points)
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
owh.. i see
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
so what next? how will i graph?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Hang on, I'm not sure about the 2 yet. Let's try equating the derivative to zero. \[\Large0=5x^{\frac23}\frac1{10x^{\frac13}}\]\[\Large5x^{\frac23}=\frac1{10x^{\frac13}}\]\[\Large5x^{\frac23}\cdot 10x^{\frac13}=1\]\[\Large50x=1\] Are you sure it's x = 2? :P
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
can you factor out 5x^(1/3) from 5x^(2/3)−10x^(−1/3)?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
You can... but why would you do that?
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
what will be the answer if you would factor out that one? 5x^(1/3) i got a little confused
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
I think it leads nowhere :)
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
owh.. lol.. so x = 1/50?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
yeah :)
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
what is the answer if i would take out 5x^(1/3) from 5x^(2/3) i really am confused on what will be the outcome
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Hang on, I may have made a mistake.
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
Okay... apparently, 2 was right.
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
sorry.
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
yehey :D so.. what to do next ?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
just like that? You're not going to ask me where my error was? :/ You didn't spot it yet... means you may well commit the same... come on, a little challenge :P
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
\[\Large0=5x^{\frac23}\frac1{10x^{\frac13}}\] I should not have put 10 in the denominator. Big mistake. Correct would be \[\Large0=5x^{\frac23}\frac{10}{x^{\frac13}}\color{green}\checkmark \]
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
you shouldn't include 10 in the denominator.. it should be on the numerator :D
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
yeah that :) sorry about that. I might be getting drowsy.
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
And as far as I know... we're done.
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
that's ok.. :))
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
We already have the critical points.
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
then how to graph?
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
whoops... you'll need to consult one of the big guys for that :3 I'm rather terrible at graphing, you see...
 one year ago

eroshea Group TitleBest ResponseYou've already chosen the best response.1
owh.. that'll be okay then.. thanks for the help! :D
 one year ago

terenzreignz Group TitleBest ResponseYou've already chosen the best response.1
No problem :)
 one year ago
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