Equation outside environments: \pi\,r^{2} π r 2 . \pi\,\rho^{3} π ρ 3

This is a theorem: hypothesis a=b a = b , thesis a\neq b. a≠ b . Clear, don’t you think?

Left as exercise for the reader.

This is real math, you know. a=b=a a = b = a .