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प्रश्न
Prove the following trigonometric identities:
`(1 - cos^2 A) cosec^2 A = 1`
उत्तर
We know `sin^2 A + cos^2 A = 1`
`sin^2 A = 1 - cos^2 A`
`=> sin^2 A . cosec^2 A`
`=> sin^2 A . 1/(sin^2 A) = 1`
∴ L.H.S = R.H.S
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