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Question

If \(\sin^2 A - \cos^2 A = \dfrac{{1}}{{2}}\), find the value of \(\cos^2 A\).

This question was previously asked in
SSC CGL 2025 Tier 2 Paper 1 Question Paper (19-Jan-2026)
The correct answer is

\(1/4\)

Using \(\sin^2 A = 1 - \cos^2 A\):

\((1 - \cos^2 A) - \cos^2 A = \dfrac{{1}}{{2}}\)

\(1 - 2\cos^2 A = \dfrac{{1}}{{2}}\)

\(2\cos^2 A = \dfrac{{1}}{{2}} \implies \cos^2 A = \mathbf{{\dfrac{{1}}{{4}}}}\)

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