# Math Help - 2(cosy-cosx)/(sinx*siny)

1. ## 2(cosy-cosx)/(sinx*siny)

how to solve this: 2(cosy-cosx)/(sinx*siny)=tan(x/2)cot(y/2)-cot(x/2)tan(y/2)

2. Originally Posted by Garas
how to solve this: 2(cosy-cosx)/(sinx*siny)=tan(x/2)cot(y/2)-cot(x/2)tan(y/2)
Look at this table and you should be able to figure show that your equality holds.

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