Posted by **Anonymous** on Thursday, November 22, 2007 at 9:01pm.

For the following equation, why cannot I not solve it? I keep getting an error.

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2cosx - 3 = 0

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I first isolated for "x"

2cosx-3 = 0

(2cosx/2) = (3/2)

x = cos^-1(3/2)

x = error? why?

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My textbook answer:

30 and 330 degrees

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