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IsTim
Group Title
Differentiate, expressing each answer using positive exponents. d) y=(4x^2+3x)^2
 2 years ago
 2 years ago
IsTim Group Title
Differentiate, expressing each answer using positive exponents. d) y=(4x^2+3x)^2
 2 years ago
 2 years ago

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lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
you know how to use chain rule right? let u = (4x^2+3x) for a while...to solve for the derivative... \(u^{2} du\) can you do that? use power rule on u..then differentiate the value of u
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
What's U? I see it in my textbook, but I don't understand.
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
u is (4x^2 + 3x) i substituted it...we're going to solve the derivative this way (u^2)(du) first..we'll solve for the derivative of u by power rule...
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
@lgbasallote: this is not integration..
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
yeah...but i find it easier using u :C
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
Here's what I wrote: h(x)=4x^2+3x, h'(x)=8x+3, g(x)=x^2 and g'(x)=2x. For some reason I put f'(x)=2(8x+3) as the final answer.
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
Wait. Where'd that comment go. I was working on that...
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
derivative of x^2 is 2x^3
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
that's the only problem with your solution...though i do not know how you got the final answer..remember that it's [g'(h(x))][h'(x)]
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
raised to 3 mimi :P have you forgotten your power rule /;) a^n = na^(n1)
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
Answer in my textbook is y'=(2(8x+3)/((4x^2+3x)^3)
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
\[y'=2(8x+3)/(4x^2+3x)^3\]
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
yup seems about right
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
I don't know how to get that...
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
(4x^2 +3x)^2..use power rule 2(4x^2 +3x)^3 now take the derivative of 4x^2 + 3x...you get 8x +3 2(4x^2 + 3x)^3 (8x+3) put 4x^2 + 3x in denom... 2(8x+3)/(4x^2+3x)^3 make sense?
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
LOL you forgot the 2 this time mimi :PPPP
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
\[y=(4x^2+3x)^{2}\] \[y' = 2(4x^2+3x)^{3}*(8x+3)\] \[y' = \frac{2}{4x^{2}+3x} *(8x+3)=>\frac{2(8x+3)}{4x^{2}+3x}\]
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
ahh that's about right :) do you get it now @IsTim ?
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
And sorry for the various typos..haven't touched derivivatives in a while..
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
for the benefit of the doubt...i'd like to write what i was starting with u... u^2 (du) derivative of u^2 is 2u^3 du = derivative of (4x^2 + 3x) = 8x + 3 substitute back u to 4x^2 + 3x 2(4x^2 + 3x)^3 (8X + 3) @Mimi_x3
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
lol, compare yoursteps to mine; which one is easier? :P
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
mine had 3 steps..yours had 3 reposts :p
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
just kdding dont kill me
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
lol, pity a poor kid who has not touched derivatives in a LONG time! :P
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
hahaha well considering as you have more medals..ill assume your method was easier :p
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
lol, only 1 medal difference dw. i was so nice that i gave you a free one. :p
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
that's the worst part mine was a pity medal :P
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
aww..i take sympathy to those who uses strange methods. :P
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
=))) it's innovation i tell you :p haha
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
Oh no. Mimi, there's a problem!
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
What's the problem?
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
The exponent of 3 on the denominator that surrounds 4x^2+3x. Where is it?
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
Woops, typo, lol..so much typos today sorry
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
i told you if you'd just use my method you wont miss that :P
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
\[y' = 2(4x^2+3x)^{3}*(8x+3)=>2*\frac{1}{(4x^{2}+3x)^{3}} *(8x+3)\] \[=>\frac{2}{(4x^{2}+3x)^{3}} *(8x+3) =>\frac{2(8x+3)}{4x^{2}+3x^{3}} \]
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
haha missed it again :P
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
Man this site should have an editing option!!!!! the last one is: \[\large \frac{2(8x+3)}{(4x^{2}+3x)^{3}} \]
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
HAHAHAHHAA =))))
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
& igba; it looks like IsTim is learning derivatives so its better not to confuse him with ambiguous methods. :P
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
okay :C i just wanted to share my innovations
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
I don't understand. How?
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
Which step you do not understand?
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
When you multiply 8x+3 into the fraction thing, how does the denominator stay the same, but have a exponent of 3? I only have the vaguest idea why.
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
I just know that the denominator is the original function, and it is being multiplied to its deriative.
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
remember how \(\large a^{n} = \frac{1}{a^n}\)?
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
that is simple algebra..which i do not know how to explain..
 2 years ago

IsTim Group TitleBest ResponseYou've already chosen the best response.0
I don't remember.
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.2
Just think as though it's simple algebra..when you go to the last step..and do it normally as you did in algebra..forget it's the derivative.
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
the rules on exponent says that if you have a variable raised to a negative exponent you take it's reciprocal and change the exponent to positive
 2 years ago

lgbasallote Group TitleBest ResponseYou've already chosen the best response.2
i.e. \(\LARGE a^{n} = \frac{1}{a^n}\) and \(\Large \frac{1}{a^{n}} = a^n\)
 2 years ago
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