Trig challenge problem: cosine of angle-sum

Sal is given cos(θ) and cos(φ) and he finds cos(θ+φ). To do that, he must first find sin(θ) and sin(φ) using the Pythagorean identity.

Trig challenge problem: maximum value

Sal solves a very complicated algebraic trig problem that appeared as problem 48 in the 2010 IIT JEE Paper I exam.

Current time: 0:00Total duration: 15:13

0 energy points

# Trig challenge problem: arithmetic progression

Sal solves a very complicated algebraic trig problem that appeared as problem 29 in the 2010 IIT JEE Paper I exam. Created by Sal Khan.