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Prove the following trigonometric identities. tan^2 θ − sin^2 θ = tan^2 θ sin^2 θ

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Questions

Prove the following trigonometric identities.

tan2 θ − sin2 θ = tan2 θ sin2 θ

Prove that:

tan2 θ − sin2 θ = tan2 θ sin2 θ

Theorem
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Solution

LHS = tan2 θ − sin2 θ

= `sin^2 θ/cos^2 θ - sin^2 θ`   `[∵ tan^2 θ = sin^2 θ/cos^2 θ]`

`=> sin^2 θ [1/cos^2 θ- 1]`

`sin^2 θ [(1 - cos^2 θ)/cos^2 θ]`

`=> sin^2 θ. sin^2 θ/cos^2 θ = sin^2 θ tan^2 θ `

LHS = RHS

Hence proved

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Chapter 18: Trigonometric identities - CHAPTER TEST [Page 427]

APPEARS IN

Nootan Mathematics [English] Class 10 ICSE
Chapter 18 Trigonometric identities
CHAPTER TEST | Q 2. | Page 427
R.D. Sharma Mathematics [English] Class 10
Chapter 11 Trigonometric Identities
Exercise 11.1 | Q 20 | Page 44

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