1. The problem statement, all variables and given/known data If one light beam is heading toward you from the right, and another is heading toward you from the left, how quickly from the perspective of the right-moving beam is the left-moving beam approaching it? 1) 0 2) c 3) 1.5c 4) 2c 2. Relevant equations (v+w) / (1 + cw/c2) 3. The attempt at a solution I tried plugging in c into the equation for both v and w but it gives me (c + c) / (1 + c2/c2) which equals 2c. It is one of the possible answers but I know nothing can go faster than c so I'm thinking the answer is probably c. Am I right? If so, why? If not, what am I doing wrong?