# Math (URGENT)

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solve for x, 0 ¡Ü x < 360

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?

• Math (URGENT) -

tan 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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