JEE Main & Advanced
Mathematics
Functions
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Functions
question_answer
If \[f(x)=\cos (\log x)\], then \[f({{x}^{2}})f({{y}^{2}})-\frac{1}{2}\left[ f\,\left( \frac{{{x}^{2}}}{2} \right)+f\left( \frac{{{x}^{2}}}{{{y}^{2}}} \right) \right]\] has the value [MNR 1992]