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प्रश्न
`1/((1+ sin θ)) + 1/((1 - sin θ)) = 2 sec^2 θ`
Prove that: `1/(1+ sin θ) + 1/(1 - sin θ) = 2 sec^2 θ`
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उत्तर
LHS =`1/((1+ sin θ)) + 1/((1 - sin θ))`
= `((1 - sin θ) + (1 + sin θ))/((1 + sin θ)(1 - sin θ))`
= `2/(1 - sin^2 θ)`
= `2/(cos^2 θ)`
= 2 sec2 θ
= RHS
Hence Proved.
Notes
Students should refer to the answer according to their questions.
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