WP 34S problem in solving f'(x)=0

[lrdheat]

That, of course, works...

I have a vague memory of changing the dX value stored in the small Greek letter d that the solve routine uses to .029 I think the default was an arbitrary.1 I can't remember the keystrokes that allow me to experiment with the dx increment used by solve. Perhaps the default or another choice for the increment would work better. Do you remember the keystrokes to set dx?