How to write formula using symbolic package?

Hey, I have one problem witch one stopping me from moving further so mayby someone of you could help me? I want to write this formula - S=C*C/4*pi but every time saying that C haven't have any value but I don't want to give any values is it possible to do it?

Answer 1

[David Hill]

s=@(c)c^2*pi/4;%function

symbolically

syms s c
eqn=s==c^2*pi/4;

Answer 2

[Walter Roberson]

syms C
S = C*C/4*pi

This requires the Symbolic toolbox.

I suggest checking to see in case the 4*pi should all be on the denominator,

syms C
S = C*C/(4*pi)

Answer 3

[Karolis Kazlauskas]

It worked, thanks for your help!