I have an interesting dilemma, my HP 50G doesn't seem to like to return the 'real' portion of negative cube roots when in exact mode.

Exact mode is helpful since it returns fractions, so I'd like to not have to switch modes or jump through hoops just to get the cube root.

In RPN mode, if I use the command 'XROOT(3,-125)' (with single quotes) and ->NUM, I get the answer I'm looking for, -5.

If I write the equation in Equation Writer (3 radical -125), it evaluates properly both in the EQW and on the stack.

However if I enter 125 +/- 3 XROOT , I get a complex equation, which simplifies to two roots. Neither of which are the answer I want.

Can someone explain in detail what's going on here? Also how can I either fix this or make it more efficient to get the real odd root of a negative number?