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Math Help - Verifying that the equation is an identity

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    Verifying that the equation is an identity

    sin(180-x)-cotxsin(x-90)=cscx
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    Quote Originally Posted by Thelema View Post
    sin(180-x)-cotxsin(x-90)=cscx
    sin(a \pm b) = sin(a)~cos(b) \pm sin(b)~cos(a)

    So:
    sin(180 - x) = sin(180)~cos(x) - sin(x) ~cos(180) = sin(x)
    and
    sin(x - 90) = sin(x)~cos(90) - sin(90)~cos(x) = -cos(x)

    So your left hand side becomes:
    sin(x) + cot(x)~cos(x)

    Can you take it from here?

    -Dan
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