any idea what then?
Try to think of a relationship between theta and phi that will get rid of one of the variables.
Then, what do you think happens when a function is at a maximum? (think calculus)
sin theta = n sin phi ?
the differential equals 0?
i already tried that - i will scan in what i did
but how do you differentiate that - i tried but came up with an absolute mess!
Hmm, maybe try using trig identities?
double angle formulas?
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