HP50G Complex Number CAS manipulations

[Hammonds]

In page 22 of the Complex Numbers with the HP49G marathon PDF, the author states:

Quote:Let's suppose, we have the equation
z^2 − z = 0 and we want to solve for z, which is complex. Using ABS
we find that the absolute value of z^2 − z is:

The answer given is a long statement of the form
sqrt(RE(Z)^4− 2RE(Z)^3+2(IM(Z)^2+1) ...etc)

My question is how is he getting the CAS to expand the original equation in this way? The most that happens for me is that I get absolute value symbols "||" placed around the z^2 - z. I have tried several combinations of CAS settings, but to no avail.

Can someone help me with the settings and key sequence? I am using an HP50G.

Thanks.