मराठी

Prove that `( Sintheta - 2 Sin ^3 Theta ) = ( 2 Cos ^3 Theta - Cos Theta) Tan Theta`

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प्रश्न

Prove that `( sintheta - 2 sin ^3 theta ) = ( 2 cos ^3 theta - cos theta) tan theta`

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उत्तर

RHS = `(2 cos^3 theta - cos theta) tan theta`

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

       =`[2(1- sin^2 theta ) -1] sin theta`

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

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

       =`( sin theta -2 sin^3 theta )`

      =LHS

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पाठ 13: Trigonometric identities - Exercises 1

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आर. एस. अग्रवाल Mathematics [English] Class 10
पाठ 13 Trigonometric identities
Exercises 1 | Q 37

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