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Question
Prove that `(cos^2θ)/(sinθ) + sin θ = "cosec" θ`.
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Solution
L.H.S. = `(cos^2θ)/(sinθ) + sin θ`
= `(cos^2θ + sin^2θ)/(sin θ)`
= `1/(sin θ)` ...[∵ sin2θ + cos2θ = 1]
= cosec θ
= R.H.S.
∴ `(cos^2θ)/(sin θ) + sin θ = "cosec" θ`
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