Derivatives on HP 42S

[lrdheat]

Yes, it becomes very hard to find the critical points as one gets further away from 0: f(x) approaches it's maximum of 1 over smaller and smaller intervals, requiring an impossibly tight interval to enter into the search far from zero!

Your program was just what I wanted. I was very close, but your program was what I was after.

Thanks again...never was exposed to the relationship between derivatives and complex numbers before you posted several years ago!

Richard