(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The problem is essentially (I've rephrased it, but this is what it is asking)

show that [ (2n_{1}cosa) / (n_{2}cosa + n_{1}cosb) ]^{2}

is equal to (sin2a sin2b) / (sin^{2}(a+b)cos^{2}(a-b))

where these are for refraction through materials and satisfy n_{1}sina=n_{2}sinb

2. The attempt at a solution

I just took pictures of my work because it would be easier than typing it all out. As far as I can tell I didn't do anything wrong up till then

first:

http://img526.imageshack.us/img526/6325/0221091218.jpg [Broken]

second:

http://img10.imageshack.us/img10/7136/0221091220.jpg [Broken]

the lines are numbered so you can refer to them easily if you need to

tl;dr:

show how [2cosasinb]^{2}= sin2a sin2b

Thanks

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# Trig Identities for Refraction

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