How do I find and classify the stationary points of a function using its derivative?

Question

The function

f(x)= 4x³ - 11x² + 6x + 5

The derivative: f'(x) = 12x² + 22x + 6

Task: Using this derivative, find and classify the stationary points of f(x).

Answer 1

The stationary points or critical points of f can be found by setting f'(x)=0.

But you have stated the derivative incorrectly: the x term is - not +.

With that change f'(x) factors easily.