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Question
What is the value of \[6 \tan^2 \theta - \frac{6}{\cos^2 \theta}\]
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Solution
We have,
`6 tan^2 θ-6/cos^2 θ= 6 tan^2 θ-6 sec ^2 θ`
= `-6 (sec^2θ-tan^2 θ)` ...{`sec ^2 θ-tan ^2 θ-1` }
= -6 × 1
= -6
\[6 \tan^2 \theta - \frac{6}{\cos^2 \theta}\]
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∴ L.H.S. = R.H.S.
