Can you calculate Pi using a Solver?

[Werner]

(12-14-2019 12:56 AM)Valentin Albillo Wrote:  Code for the HP-71B, where FNROOT (Find Root) is the "official" HP-71B's "Solver":

     1   DEF FNF(X) = FNROOT(1, 1, GAMMA(FVAR) - X)
     2   DISP FNROOT(3, 4, FNF(SQR(FVAR)) - 1/2)

>RUN

          3.14159265359

This produces as a root the theoretically exact (not an approximation) value of Pi.

V.

Hi, Valentin!
Why not just use GAMMA(0.5) - SQRT(X) = 0 as the generating equation?
I don't own a 71, but then it ought to be something like
DISP FNROOT(3, 4, GAMMA(1/2) - SQR(FVAR) )

Cheers, Werner