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Popular >

cos(2x)(2cos(x)+1)=0

Solution

cos (2 x) (2 cos (x) + 1) = 0

Solution

x = \frac{π}{4} + πn, x = \frac{3 π}{4} + πn, x = \frac{2 π}{3} + 2 πn, x = \frac{4 π}{3} + 2 πn

+1

Solution steps

cos (2 x) (2 cos (x) + 1) = 0

Solving each part separately

cos (2 x) = 0 or 2 cos (x) + 1 = 0

cos (2 x) = 0 : x = \frac{π}{4} + πn, x = \frac{3 π}{4} + πn

2 cos (x) + 1 = 0 : x = \frac{2 π}{3} + 2 πn, x = \frac{4 π}{3} + 2 πn

Combine all the solutions

x = \frac{π}{4} + πn, x = \frac{3 π}{4} + πn, x = \frac{2 π}{3} + 2 πn, x = \frac{4 π}{3} + 2 πn

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