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Derivatives as Functions
2. Intro to Derivatives / Derivatives as Functions / Problem 3
Problem 3

The following formulas for f(a)f_{-}^{\prime}\left(a\right) and f+(a)f_{+}^{\prime}\left(a\right) represent the left- and right-sided derivatives of a function at a point aa, respectively:
f(a)=limh0f(a+h)f(a)hf_{-}^{\prime}\left(a\right)={\displaystyle\lim_{h\to0^{-}}{\frac{f(a+h)-f(a)}{h}}}, f+(a)=limh0+f(a+h)f(a)hf_{+}^{\prime}\left(a\right)={\displaystyle\lim_{h\to0^{+}}{\frac{f(a+h)-f(a)}{h}}}
Consider f(x)={6x2   if x23x4   if x>2f\left(x\right)=\begin{cases}6-x^2~~~\text{if}~x\leq{2}\\ 3x-4~~~\text{if}~x\gt{2}\end{cases}. Find f(a)f_{-}^{\prime}\left(a\right) and f+(a)f_{+}^{\prime}\left(a\right) at a=2a=2.

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