can someone help me solve for x for this equation

Question

(0.5)(((cos(180-x))^(2))(cos(90-x))^(2))=0.0500

Answer 1

cos(180-x) = -cos(x)
cos(90-x) = sin(x)

so you have

(0.5)cos^2(x)sin^2(x) = 0.05
cos^2(x) sin^2(x) = 1/10
sin^2(2x) = 1/40
sin(2x) = ±1/(2√10)

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