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`(1-tan^2 Theta)/(Cot^2-1) = Tan^2 Theta`

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Question

`(1-tan^2 theta)/(cot^2-1) = tan^2 theta`

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Solution

LHS = `(1- tan^2 theta)/(cot^2 theta-1)`

      =`(1-(sin^2 theta)/(cos^2 theta))/((cos^2 theta )/(sin^2 theta)-1)`

      =`((cos^2 theta - sin^2 theta)/(cos^2 theta))/((cos^2theta-sin^2 theta)/(sin^2 theta))`

     =`(sin^2 theta)/(cos^2 theta)`

     = tan2 𝜃 
     = RHS

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Chapter 13: Trigonometric identities - Exercises 1

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R.S. Aggarwal Mathematics [English] Class 10
Chapter 13 Trigonometric identities
Exercises 1 | Q 18.2

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