1. The problem statement, all variables and given/known data _{sin (90 - θ + λ) = sin90cos(θ + λ) - cos90sin(θ + λ) = cos(θ + λ) The book says cos(θ - λ) So are we both right and if so how can I manipulate mine to look like the books answer.} 2. Relevant equations 3. The attempt at a solution
Ah my old friend Tim. I was surprised that 100's of people looked at this and nobody answered. I suspected this was a super easy question, as you just proved. Thank you very much.