How do you simplify $cot(x+y)-sin(x+2y)$ to trigonometric functions of x and y?

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Answer 1 · 2016-08-10T15:42:08

$cos(x+y)-sin(x+2y)$

$=cosxcosy-sinxsiny-sinxcos2y-cosxsin2y$

$=cosxcosy-sinxsiny-sinx(2cos^2y-1)-2cosxsinycosy$

$=cosxcosy-sinxsiny-2sinxcos^2y+sinx-2cosxsinycosy$

How do you simplify cot(x+y)-sin(x+2y)cot(x+y)-sin(x+2y) to trigonometric functions of x and y?