Rectangular ne polar

Akatonnyeze kasobola okuwandiikibwa mu $P(x,\ y)$, nga $\displaystyle x$ eri ku ludda ne $\displaystyle y$ waggulu, oba mu $P(r,\ \theta)$, nga kirimu obuwanvu $\displaystyle r$ n'ensonda $\displaystyle \theta$. $r=\sqrt{x^{2}+y^{2}}$. Bwe tudda ku ludda olulala, $x=r\cos\theta$. Kalakuleta ekyusa mu njira zombi, era etereka ebyokuddamu mu materekero $\displaystyle X$ ne $\displaystyle Y$.