Hi;

In this form, I do not think of a way to store it in RPN format. Anyway, you can change it from C = (A^2 + B^2)^1/2 to (A^2 + B^2)^1/2 - C. In this case, one of the solutions (expect many) would be:

Consider C and B already stored in the current directory

LEVEL1 LEVEL2

« -> A

«

B B

SQ (x^2) B^2

A A B^2

SQ (x^2) A^2 B^2

+ B^2+A^2

.5 .5 B^2+C^2

^ (y^x) (B^2+A^2)^.5

C C (B^2+A^2)^.5

- (B^2+A^2)^.5 - C

»

»

Given A in the stack, this program returns the expression value. If it returns zero, you have a root. To automate the process, it's necessary to use the ROOT command, and you'll need an extra procedure.

Hope it helps. (I did not check this info, I have neither the manuals, nor the calcs in hand now. Maybe there are some errors)