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प्रश्न
Prove the following trigonometric identities.
`"cosec" theta sqrt(1 - cos^2 theta) = 1`
Prove the following:
`"cosec" theta sqrt(1 - cos^2 theta) = 1`
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उत्तर
We know that `sin^2 theta + cos^2 theta = 1`
So,
LHS = `"cosec" theta sqrt(1 - cos^2 theta)`
= `"cosec" theta sqrt (sin^2 theta)`
= cosec θ . sin θ
`1/sin theta xx sin theta`
= 1
= RHS hence proved.
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Activity:
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= (sin2A + cos2A) `(square)`
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