Back to high-school Trig basics

Given this diagram, i need to find the coordinate X,Y.

Maths problem

Essentially, the problem is when a line is drawn from (0,0) extending length radius (r) to the intersection of the circle, and given an angle t, find point (x,y).

i know i used to do this kind of thing easy back in high-school but all this database development and ASP.NET has made my core maths soft.

took me a bit, but i got it.

    sin(t) = x/r,
    x = r.sin(t)

    cos(t) = y/r,
    y = r.cos(t)

reason? extend (x,y) downward such that it intersects with the x-axis (call it point A). you now have two parallel lines, and angle t is the interior opposite angle of a right-angle triangle between A, (0,0) and (x,y). The rest is SOH-CAH.

i thought about it for a while, but this proves i really need to brush up on my high-school maths. sheesh.

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