1. The problem statement, all variables and given/known data How do you derive the following equation given I/Io= (I/N2)[(sinNØ/2)/(sinØ/2)]2 given that Ø= (2πdsinΘ)/λ 2. Relevant equations Ø= (2πdsinΘ)/λ d=λ/sinΘ 3. The attempt at a solution I have tried substituting Ø into the equation as well as d=λ/sinΘ, but I always seem to make the equation equal to 1 or 0 and this really isn't what I'm looking for. Does this equation come from an amplitude equation using trig identities of some sort?