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 one year ago
can someone help me solve this problem ?
let f(x)= (x^3+3x+8)^2
F'(x)=
F'(2)=
 one year ago
can someone help me solve this problem ? let f(x)= (x^3+3x+8)^2 F'(x)= F'(2)=

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hartnn
 one year ago
Best ResponseYou've already chosen the best response.1do you know the chain rule ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0not really sure with the chain rule..

sam1194
 one year ago
Best ResponseYou've already chosen the best response.0need to learn that then to do a question of this type

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0yes, that's why I'm trying to learn it here.. if that helps.

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1let me give you a similar example, if \(f(x) = (ax^2+bx+c)^3 \) then by chain rule, \(f'(x)=3(ax^2+bx+c)^2 (ax^2+bx+c)' \\ =3(ax^2+bx+c)^2(2ax+b) \) got this ?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1by definition, \(f(g(x))' = f'(g(x)) \times g'(x)\)

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1so try once for your Q, maybe.. ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0you dont subtract the exponent n1?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1i made the exponent n1 in the Q, ax^2+bx+c had exponent 3, in the answer i became 2, right ?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1for x^n, the derivative is \((x^n)'=n x^{n1}\)

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0okay... sort of there. but then the second equation next to it confused me a little.

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1yeah, from the definition, i needed to multiply by the derivative of inner function also (g'(x)) so ,i multiplied by derivative of ax^2+bx+c which is 2ax+b

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1in your Q, you'll multiply by (x^3+3x+8)

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1**by the derivative of (x^3+3x+8)

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0so the derivative for F'(x) would be.. (3x^2+3x+8)?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1no... you have to first derivate the out function, (x^2), then multiply the derivative of each term of x^3+3x+8 first tell whats the derivative of x^2

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1so, derivative of (x^3+3x+8)^2 will be 2(x^3+3x+8) *(derivative of x^3+3x+8 ) , right ? can you differentiate, x^3+3x+8 ?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1derivative of x^3+3x+8 lets take it term by term derivative of x^3 =... ?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1no... derivative of x^n = nx^{n1}

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.02? i really am so confused

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1derivative of a constant = 0 so derivative of 8 is 0 so, derivative of x^3+3x+8 = 3x^2+3 right ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0i understand that better.

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0now what if 2 was plugged in

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1so, we have : derivative of (x^3+3x+8)^2 will be 2(x^3+3x+8) *(derivative of x^3+3x+8 ) , = 2(x^3+3x+8) * (3x^2+3) got this ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0i thought the derivative of f '(x) is 3x^2+3

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1didn't i mention to u the chain rule ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0oh yeah, multiple use the one before and after

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1so any doubts now ? that would be your final answer...

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0nope no doubts. now what if the problem was f ' (2)= ?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0i did but im still not sure what am i suppose to do.

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0i plug them in but i get confused with the derivative and actually multiplying it out.

hartnn
 one year ago
Best ResponseYou've already chosen the best response.12(x^3+3x+8) * (3x^2+3) put x=2 2(2^3+3*2+8) * (3*2^2+3) =... ?

hartnn
 one year ago
Best ResponseYou've already chosen the best response.1i get 660 :P using google https://www.google.co.in/search?q=2(2%5E3%2B3*2%2B8)+*+(3*2%5E2%2B3)&aq=f&oq=2(2%5E3%2B3*2%2B8)+*+(3*2%5E2%2B3)&aqs=chrome.0.57.192&sourceid=chrome&ie=UTF8

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0thank you. thats correct

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0would it be possible to know the answer of a few problems because I would need to sign off and practice by hand but I would like to check my work and see if they're correct.
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