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प्रश्न
`(1+ cos theta)(1- costheta )(1+cos^2 theta)=1`
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उत्तर
LHS = `(1+costheta )(1-cos theta)(1+ cot^2 theta)`
=` (1-cos^2 theta) cosec^2 theta`
=` sin^2 theta xx cosec^2 theta`
=` sin^2 theta xx1/(sin^2 theta)`
=1
= RHS
APPEARS IN
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