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Question
Write the value of `(1+ tan^2 theta ) ( 1+ sin theta ) ( 1- sin theta)`
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Solution
`(1+ tan^2 theta )(1+ sin theta )(1- sintheta)`
=` sec^2 theta (1- sin^2 theta )`
=`1/ cos^2 theta xx cos^2 theta`
= 1
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