Functions and graphs

Question

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

Answer 1

If the angle is θ then:

 

tan θ = y/x = x²/x = x

 

The coordinates of P are then:

 

x = tan θ

 

y = tan² θ