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प्रश्न
Prove that cot2θ × sec2θ = cot2θ + 1.
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उत्तर
L.H.S. = cot2θ × sec2θ
= `(cos^2θ)/(sin^2θ) xx 1/(cos^2θ)`
= `1/(sin^2θ)`
= cosec2θ
= 1 + cot2θ ...[∵ 1 + cot2θ = cosec2θ]
= R.H.S.
∴ cot2θ × sec2θ = cot2θ + 1
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