### Home > APCALC > Chapter 4 > Lesson 4.2.4 > Problem4-86

4-86.

Review Hanah’s method for setting up a derivative. Use Hanah’s definition of derivative from Lesson 3.2.1 to differentiate $f(x)=4x^2-9x-1.$

$f'(x)=\lim \limits_{h\rightarrow 0}\frac{f(x+h)-f(x-h)}{2h}$