1. The problem statement, all variables and given/known data A plane is approaching an observer from an altitude of 5 mi at a dx/dt of 600 mi/h. Find the d(theta)/dt when theta is 30 degrees, 60 degrees, and 75 degrees. 2. Relevant equations tan(theta) = x/y 5csc(theta) = r 3. The attempt at a solution For my d(theta)/dt I had the formula of 3000/(5csc(theta))^2 The answers I had were wrong according to the text. Please help.