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प्रश्न
`(sec^2 theta -1)(cosec^2 theta - 1)=1`
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उत्तर
LHS = `(sec^2 theta -1)(cosec^2 theta-1)`
=`tan^2 theta xx cot^2 theta ( ∵ sec^2 theta - tan^2 theta = 1 and cosec^2 theta - cot^2 theta =1)`
=` tan^2 theta xx1/(cos^2theta)`
=1
=RHS
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संबंधित प्रश्न
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`cot^2 A cosec^2B - cot^2 B cosec^2 A = cot^2 A - cot^2 B`
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= `cosθ/sinθ + square/cosθ`
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= `1/(sinθ xx cosθ)` ....... ∵ `square`
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= `square xx secθ`
∴ L.H.S. = R.H.S.
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