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Sin2θ+cos4θ=cos2θ+sin4θ

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Question

`sin^2 theta + cos^4 theta = cos^2 theta + sin^4 theta`

Sum
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Solution

LHS = `sin^2 theta + cos ^4 theta`

      =`sin^2 theta + ( cos ^2 theta )^2`

      =`sin^2 theta + (1- sin^2 theta)^2`

      =` sin^2 theta + 1 -2  sin^2 theta + sin ^4 theta`

      =`1-sin^2 theta + sin^4 theta`

     =`cos^2 theta + sin^4 theta`

    = RHS
Hence, LHS = RHS

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Chapter 13: Trigonometric identities - Exercises 1

APPEARS IN

R.S. Aggarwal Mathematics [English] Class 10
Chapter 13 Trigonometric identities
Exercises 1 | Q 17.2

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