MathDB
Heated Argument

Source: 2014 AIME I Problem 7

March 14, 2014
trigonometrycalculusderivativevectorratioanalytic geometrygraphing lines

Problem Statement

Let ww and zz be complex numbers such that w=1|w| = 1 and z=10|z| = 10. Let θ=arg(wzz)\theta = \arg\left(\tfrac{w-z}{z}\right). The maximum possible value of tan2θ\tan^2 \theta can be written as pq\tfrac{p}{q}, where pp and qq are relatively prime positive integers. Find p+qp+q. (Note that arg(w)\arg(w), for w0w \neq 0, denotes the measure of the angle that the ray from 00 to ww makes with the positive real axis in the complex plane.