Math
posted by Daisy .
Find all real solution of the equation sin^2x = 2+2cosx

Math 
Steve
since sin^2 = 1cos^2,
1cos^2 = 2 + 2cos
cos^2 + 2cos  3 = 0
(cos+3)(cos1) = 0
cos=1, so x = 0,2pi,4pi,...
why not 3?
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