Without using tables, verify that : 60= 1- ^2 30^ 1+ ^2 30^ =1 2 … - Vidyadip

Question

Without using tables, verify that : $\cos 60=\frac{1-\tan ^2 30^{\circ}}{1+\tan ^2 30^{\circ}}=\frac{1}{2}$.

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Answer

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