[Calculus] Find relative extrema and points of inflection. State where the function is increasing or decreasing and where it is concave up or concave down.
f(x)=2x^2-x^4

Question

[Calculus] Find relative extrema and points of inflection. State where the function is increasing or decreasing and where it is concave up or concave down.
f(x)=2x^2-x^4

anonymous · Answer

I found the critical points of x = -1, 0, and 1. I threw out 0 because it is between two other critical points and tried to find the relative extrema for -1 and 1, but neither one came up with relative extrema. I plugged the equation into WolframAlpha and the graph clearly has relative extrema. What am I doing wrong?