In problem a find all x-values where the slope of the

Question

In Problem (a) find all x-values where the slope of the tangent equals zero, (b) find points (x, y) where the slope of the tangent equals zero, and (c) use a graphing utility to graph the function and label the points found in part (b).

f(x) = x⁶ - 6x⁴ + 8