I'm having difficulties with a few identity problems and I wanted to make sure I'm doing the ones I believe I did correctly, correctly...(adsbygoogle = window.adsbygoogle || []).push({});

1. (cos^3x)+(sin^2x)(cosx)

(cosx)(cos^2x)+(sin^2x)(cosx)

2cosx

2. (1+cosy)/(1+secy)

(1+cosy)/(1+1/cosy)

(1+cosy)/(1+cosy)

1

3. (tanx)/(secx)

(sinx/cosx)/(1/cosx)

(sinx/cosx)(cosx)

sinx

4.(secx-cosx)/(tanx)

(secx-cosx)(cosx/sinx)

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

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

(1/sinx)

cscx

5.(sinx/cscx)+(cosx/secx)

(sinx/1/sinx)+(cosx/1/cosx)

(sinxsinx)+(cosxcosx)

sin^2x+cos^2x

1

6. (1+sinx/cosx)+(cosx/1+sinx)

(1+sinx/1+sinx0(1+sinx/cosx)+(cosx/cosx)(cosx/1+sinx)

(1+2sinx+sin^2x+cos^2x)/(1+sinx)(cosx)

(2+2sinx)/(1+sinx)(cosx)

(2+sinx)/(cosx)

2tanx

7. (tanx)(cosx)(cscx)

(sinx/cosx)(cosx)(1/sinx)

1

The ones that I'm not too sure about are 2 and 8. I feel pretty confident about the other ones, but I wanted to make sure I'm doing them correctly.

Thanks a lot to anybody that helps.

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# Homework Help: Need help with some identity problems

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