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April 19, 2014

April 19, 2014

Posted by **John** on Friday, December 16, 2011 at 2:55am.

tan2x+1=0

My answers: 22.5, 157.5, 202.5, 337.5

Textbook: 67.5, 157.5, 247.5, 337.5

I don't understand. Am I wrong?

Thanks for your help.

- Math (URGENT) -
**Damon**, Friday, December 16, 2011 at 5:01amtan 2 x = -1

tan is negative in quadrants 2 and 4

2x = 135, 315, 495, 675

now divide those by 2

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