Question

Let f be the function defined as f(x) = 3x2− 4.
a. Use the definition of the derivative to find f′(x)

Answer 1

Hint: f(x+h) - f(x)/(x-h)

Answer 2

First principle.

Answer 3

I know the definition I just don't know how it would be written with the equation.

Answer 4

Oh Okay. Put (x+h) instead of in f(x+h) So your eqn becomes {3(x+h)^2 - 4} - {3x^4-4}

Now solve..!! Please taken care of -ve sign..;)

Answer 5

so the equation would look like this
\[[3(x+h)^{2}-4]-[3x ^{4}-4]/h\]
Right ?

Answer 6

In the denominator it should be (x-h) instead of 'h'. I believe you've made a typo error.

Answer 7

In the numerator it should be [3x^2 -4} not x^4.! Now you just need to expand and cancel.

Answer 8

Ok let me know if I'm doing it right so would I do