Question

Find the number of solutions of the equation 2cos²(x/2)sin²(x) = x² + 1/x² , 0 < x ≤ π/2 .

Joshi sir comment

max of sin and cos are 1 so max of left is 2

but x² + 1/x² ≥ 2x(1/x) = 2

so only solution will be obtained for 2cos²(x/2)sin²(x) = 2

so (1+cosx)(1-cos²x) = 2 which is impossible,so i think no solution

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