Real function/Extrema/4x^3+3x^2-x+2/Tangent from -3 to 3/Exercise

Consider the function

$f:ℝ⟶ℝ,x⟼f(x)=4x^3+3x^2-x+2.$

Find the point $a\in [-3,3]$ such that the tangent of the function at $a$ is parallel to the secant between $-3$ and $3$.

Create a solution