Pre-Calc : Verify the Identity

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Verify the Identity:
sin(x+π)/cos(x+3π/2) =tan^2x-sec^2x

I've done:
sinxcosπ+cosxsinπ
/
cosxcos(3π/2) - sinxsin(3π/2)

sinx(-1) + cosx(0)
/
cosx(0)- sinx(-1)

-sinx/sinx


What do I do from here? Or what did I do wrong?

  • Pre-Calc : Verify the Identity -

    first, note that since sec^2 = 1+tan^2, the right side is just -1

    On the left, you have arrived at sinx/sinx = -1

    Done

  • Pre-Calc : Verify the Identity -

    thank you!

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