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`(1+ Cos Theta)(1- Costheta )(1+Cos^2 Theta)=1`

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Question

`(1+ cos theta)(1- costheta )(1+cos^2 theta)=1`

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Solution

LHS = `(1+costheta )(1-cos theta)(1+ cot^2 theta)`

       =` (1-cos^2 theta) cosec^2 theta`

       =` sin^2 theta xx cosec^2 theta`

       =` sin^2 theta xx1/(sin^2 theta)`

      =1

     = 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 4.1

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