I've received an assignment to investigate the polar coordinate system compared to the cartesian one.

Theres a question that asks you to investigate into how to convert polar coordinates into cartesian.

From my text book, I know in Polar coordinates, that if (d,è) is a point, where is d the distance and è is the angle, to convert into cartesian,

x = d cos è
y = d sin è

but I don't know how to prove it, or even explain it

1 answer

make a diagram such as this

http://www.kwon3d.com/theory/crdsys/polar.html