1) Solve

(sinx)/(cot^2x) - (sinx)/(cos^2x)

2) Prove

tan^2x - sin^2x = tan^2x*sin^2x

3) Prove

sin(x - π/2) = -cosx

Thanks for any help!

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- April 19th 2009, 05:05 PMlive_laugh_luv27Proving/Solving trig equations
1) Solve

(sinx)/(cot^2x) - (sinx)/(cos^2x)

2) Prove

tan^2x - sin^2x = tan^2x*sin^2x

3) Prove

sin(x - π/2) = -cosx

Thanks for any help! - April 19th 2009, 05:30 PMskeeter
- April 19th 2009, 05:36 PMlive_laugh_luv27
Thanks so much..you've been really helpful :)

- April 19th 2009, 06:22 PMlive_laugh_luv27one question..
sorry, i just have one question.

Could you please explain how you did #2? I can't get past the second step.

How did you get tan^2x(1-cos2x) to equal tan^2x - sin^2x? After I distribute the tan^2x, I'm not sure what to do.

Thanks! - April 19th 2009, 06:31 PMskeeter
- April 19th 2009, 06:38 PMlive_laugh_luv27
great, thanks!