Posted by **Phil-- HELP NEEDED ASAP** on Friday, May 10, 2013 at 9:43am.

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 -
**Steve**, Friday, May 10, 2013 at 10:53am
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 -
**Phil-- HELP NEEDED ASAP**, Friday, May 10, 2013 at 12:03pm
thank you!

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