Question

Find the derivative of f(x) = 8x^2 + 11x at x = 7.

Answer 1

how do you do this?

Answer 2

find f'(x) which is = 16x +11
then sub x=7 in f'(x)
so answer is 16(7)+11

Answer 3

using the power rule \[f'(x)=2(8)x^1+1(11)x^0 =16x+11\]

Answer 4

first you need to find the derivative of f(x) = 8x^2 + 11x, to do this
\[f \prime(x) = 2*(8x ^{(2-1)}) + 1*11x^{(1-1)}\]
which is \[f \prime(x) = 16x + 11\]
then let x = 7 gives us
\[f \prime(7) = 123\]