Can you calculate Pi using a Solver?

[Gamo]

HP-15C have a SOLVE function but I find the better way
to find the estimated value of Pi just by using the GAMMA function.

Formula: [ Γ(1/2) ]^2 = Pi

To find the estimated value of Pi follow this keystroke steps:

[.] 5 [ENTER] 1 [-] display -0.5 [x!] display 1.772453851 [x^2]

display 3.141592654

Answer is the same from the built-in Pi function.

Gamo