## Pi

Pi, or $\pi$, is commonly used in the context of circles in geometry. In particular, the circumference $C$ of a circle that has a diameter $d$ is $C = \pi d$. Also, the…

What is the Pythagoras theorem? It is $a^2 + b^2 = c^2$. Here, $a$, $b$ and $c$ are the lengths of a right triangle. Note that $c$ is the hypotenuse of the…