Science:Math Exam Resources/Courses/MATH110/April 2016/Question 09 (a)/Statement

Suppose that the function $f$ is differentiable for all $x$ and that $f(-1)=-1$ and $f(2)=5$.

(a) Prove that there is a point on the graph of $f$ at which the tangent line is parallel to the line with the equation $y=2x$. Make sure you state what theorem(s) you use to support your claim and why they apply.