# Show "step-by-step" button in W|A Pro?

GROUPS:
 I just purchased a Pro plan because I wanted to see the step-by-step solution to "integral of (z^2 * (1/sqrt(2*pi)) * exp(-z^2/2)) from negative infinity to infinity" which includes an integration by parts. However, I don't see a "Step-by-step" button even after logging out and back in a couple of times. All I get is the answer (1). Any ideas?
 Gianluca Gorni 1 Vote The indefinite integral involves the error function Erf, a special function. The step-by-step approach may be limited to elementary integrals.