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` Tan^2 Theta - 1/( Cos^2 Theta )=-1` - Mathematics

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Question

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

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Solution

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

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

    =`(sin ^2 theta-1)/(cos^2 theta)`

   =` (-cos^2 theta )/(cos^2 theta)`

   =  -1

  = RHS

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Chapter 8: Trigonometric Identities - Exercises 1

APPEARS IN

R.S. Aggarwal Mathematics [English] Class 10
Chapter 8 Trigonometric Identities
Exercises 1 | Q 5.2

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