Chapter 4: Applications of Derivatives - Section 4.2 - The Mean Value Theorem - Exercises 4.2 - Page 198: 27

Yes

The Roll's Theorem states that there is a point $c$ taken as a constant when the function $f(x)$ is differentiable with $f'(x)=0$. This means that $f'(c)=\dfrac{f(b)-f(a)}{b-a} \ne 0$, which contradicts to $f'(x)=0$ for all $x$. Thus, we have when $f(x)=3$ then $f'(x)=0$ for all $x$.So, this might be saying true for when $f(x)=f(-1)=3$ for all $x$.