A point in the first quadrant lies on the parabola y = x^2. Express the coordinates of P as function of the angle of inclination of the line joining P to the origin

1 answer

The angle joining P to the origin is
A = tan^-1 (y/x)

You can invert that to read
y = x tan A
In addition to that, along the parabola,
y = x^2

Therefore
x = tan A and
y = tan^2 A