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?
The indefinite integral involves the error function Erf, a special function. The step-by-step approach may be limited to elementary integrals.
I've sent the Wolfram|Alpha team a note about your suggestion by filling out the Feedback form at the bottom of the Wolfram|Alpha page with your example.
Right now, it doesn't look like step-by-step integration handles special functions like erf.