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Question
(sinx/1-cosx)-(sinx/1+cosx)= 2cotx
I'm getting stuck with this problem because I am not getting the same answer, I am getting 2cotx+sinx,
If you can show me the steps it will be great thank you
It's easy,actually.
sinx/(1-cosx) - sinx/(1+cosx)
=(sinx + sinxcosx - sinx + sinxcosx)/(1 - cosx)(1 + cosx)
=2sinxcosx/(sinx)^2
=2cosx/sinx
=2cotx
Next time, try to find out why yourself.In this case, you probably made a mistake of the sign before the second sinx. It should be negative and thus cancel out with the first one.
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Chen Min
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