Question

If f(x) = 2x³ + x² - 3x + 4 , what is f'(2) ?

Answer 1

f'(2) = 25

Explanation:

differentiate f(x) using the power rule

`(d)/(dx)` ( a
`x^(n)` ) = na
`x^(n-1)` and
`(d)/(dx)` ( constant) = 0

f(x) = 2x³ + x² - 3x + 4

f'(x) = 3× 2x² + 2x - 3 = 6x² + 2x - 3 , then

f'(2) = 6(2)² + 2(2) - 3

= 6(4) + 4 - 3

= 24 + 1

= 25