Question

Derivative question

Answer 1

Find f'(a)
\[f(x) = 3x^2 - 4x + 1\]

We are supposed to use the derivative formula. So...
3(a+h)^2 - 4(a+h) + 1 all over h
Right? Then I distributed, etc. and nothing seems to be canceling...

Answer 2

it would be f(a+h) - f(a) on the top

Answer 3

Your missing the -f(a) which does most of the cancelling.

Answer 4

Ohh I think I see what I did wrong.. hold on

Answer 5

The derivative is 3x + 3h - 4 right? Or should I plug in 0?

Answer 6

well h is set to 0

Answer 7

you should get 6x-4 though

Answer 8

or rather 6a-4

Answer 9

I got 3a - 4
Where is the 6 coming from? D:

Answer 10

lets see if i expand i get 3a^2+6ah+3h^2-4a-4h+1-3a^2+4a-1 for the numerator.

Answer 11

so 6ah+3h^2-4h after simplifying

Answer 12

for the numerator

Answer 13

Oh! :P
Right. Thanks :)