HP 50G "Bad Argument Value" - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: General Forum (/forum-4.html) +--- Thread: HP 50G "Bad Argument Value" (/thread-8725.html) HP 50G "Bad Argument Value" - root07 - 07-23-2017 08:05 PM SOLVE(X^40=13^X,X) -> SOLVE Error: Bad Argument Value. How to solve the equation? RE: HP 50G "Bad Argument Value" - Joe Horn - 07-24-2017 05:01 AM I'd suggest using the numeric solver (ROOT) instead of SOLVE or SOLVEVX because those use CAS logic to look for a symbolic result. ROOT uses numeric methods to find one root at a time near a given initial guess. In RPN mode: 'X^40=13^X' 'X' 1 (or whatever guess you want to start at) ROOT --> 1.07109628939 With an initial guess of -1 you get another root, -0.941418703497 Also try an initial guess of 65. Finding ALL the roots is left as an exercise for the student. ;-) RE: HP 50G "Bad Argument Value" - BartDB - 07-24-2017 05:32 PM You can also use the interactive numerical solver: Red Shift NUM.SLV, then select 1. Solve equation (Initial guesses can be entered for X before selecting F6:SOLVE) This is useful if you want to quickly try just a few guesses. However, the ROOT command can be used in a program (for example if you wish to create a program that tries a several guesses (for instance it has an input for both the equation and a list of guesses)).