1. The problem statement, all variables and given/known data The question asks to express vector C in terms of A, B, and theta. 2. Relevant equations I would guess the relevant equations to be trig equations. 3. The attempt at a solution I found sin[(180-theta)/2] = k/B (k is a variable I set to equal the right bisected part of C when the angle c was divided in two). Also, sin[(180-theta)/2]= j/A. c= 180 - theta. After that however, I don't know how to incorporate theta without using phi. Can you assume that a line stretching from the angle to to make a right angle with vector C bisects the angle into two equal angles? That was how I attempted to solve the problem, but I'm not sure if that works. Any help would be greatly appreciated. Thanks in advance.