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Prove the Following Trigonometric Identities. (Sec^2 θ − 1) (Cosec^2 θ − 1) = 1 - Mathematics

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Questions

Prove the following trigonometric identities.

(sec2 θ − 1) (cosec2 θ − 1) = 1

Prove the following:

(sec2 θ − 1) (cosec2 θ − 1) = 1

Theorem
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Solution

We know that

sec2 θ − tan2 θ = 1

cosec2 θ − cot2 θ = 1

So,

(sec2 θ − 1)(cosec2 θ − 1) = tan2 θ × cot2 θ

= (tan θ × cot θ)

= `(tan θ xx 1/tan θ)^2`

= (1)2

= 1

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Chapter 18: Trigonometric identities - Exercise 18A [Page 423]

APPEARS IN

Nootan Mathematics [English] Class 10 ICSE
Chapter 18 Trigonometric identities
Exercise 18A | Q 2. | Page 423

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