>>13484326cos(?) and sin(?) are the x and y cooordinates of the Unit circle given you have travelled ? distance on that unit circle, starting from (1, 0) and going counter-clockwise at a unit speed.
You can generalize this for a circle of radius R. Then you'll have to cover R times the distance of the unit radius case, i.e. to get cos(1), sin(1) you'd have to travel the distance of 1 Radius (going at speed R).
And that's what Radians are: it's how many radii you've travelled on the circle.
This generalization is pointless and all mathematicians just use the unit circle as a reference.
