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प्रश्न
Write the value of `cosec^2 theta (1+ cos theta ) (1- cos theta).`
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उत्तर
`cosec^2 theta (1+ cos theta )(1- cos theta)`
= `cosec^2 theta (1- cos^2 theta)`
=`1/ sin^2 theta xx sin^2 theta `
= 1
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