So I found the derivative of an expression and I cannot figure out how to simplify the final answer into the desired form. I got -csc^2(X)/(1+cotx)^2. Now how do I simplify this into -1/(sinx+cosx)^2. Help, it's killing me ahha. Thanks!

- 1/sin^2

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(1 + cos/sin)^2

-1
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sin^2 [ (1+cos/sin)(1+cos/sin)]

-1
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(sin+cos)(sin+cos)