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If Cosec θ = 2x and 5 ( X 2 − 1 X 2 ) 2 ( X 2 − 1 X 2 ) - Mathematics

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Question

If cosec θ = 2x and \[5\left( x^2 - \frac{1}{x^2} \right)\] \[2\left( x^2 - \frac{1}{x^2} \right)\] 

Sum
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Solution

Given: 

`cosecθ=2x, cot θ2/x` 

We know that, 

`cosec^2 θ-cot^2 θ=1`

⇒` (2x)^2-(2/x)^2=1` 

⇒` 4x^2-4/x^2=1` 

⇒ `4(x^2-1/x^2)=1` 

⇒`2xx2xx(x^2-1/x^2)=1` 

⇒ `2(x^2-1/x^2)=1/2`

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Chapter 11: Trigonometric Identities - Exercise 11.3 [Page 55]

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RD Sharma Mathematics [English] Class 10
Chapter 11 Trigonometric Identities
Exercise 11.3 | Q 23 | Page 55

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Solution :

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