हिंदी

If Cos θ + Cot θ = M and Cosec θ – Cot θ = N, Prove that Mn = 1

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प्रश्न

If cos θ + cot θ = m and cosec θ – cot θ = n, prove that mn = 1

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उत्तर

LHS = mn

`= (cosec theta + cot theta) (cosec theta - cot theta)`

`= cosece^2 theta - cot^2 theta`

= 1    [∵ `(1 + b)(a - b) = a^2 - b^2 cosec^2 theta - cot^2 theta = 1`]

=RHS

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अध्याय 11: Trigonometric Identities - Exercise 11.1 [पृष्ठ ४७]

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आर.डी. शर्मा Mathematics [English] Class 10
अध्याय 11 Trigonometric Identities
Exercise 11.1 | Q 81 | पृष्ठ ४७

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