मराठी

Prove the following trigonometric identities. cos^2 A + 1/(1 + cot^2 A) = 1

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प्रश्न

Prove the following trigonometric identities.

`cos^2 A + 1/(1 + cot^2 A) = 1`

सिद्धांत
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उत्तर

L.H.S. = `cos^2 A + 1/(1 + cot^2 A)`

= `cos^2 A + 1/("cosec"^2 A)        ...[1 + cot^2A = "cosec"^2 A]`

= `cos^2 A + sin^2 A     ...[1/("cosec" A) = sin A]`

= `cos^2 A + sin^2 A`

= 1  (R.H.S.)       ...`[sin^2 A + cos^2A = 1]`

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 11: Trigonometric Identities - EXERCISE 11.1 [पृष्ठ ११.३४]

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आर.डी. शर्मा Mathematics [English] Class 10
पाठ 11 Trigonometric Identities
EXERCISE 11.1 | Q 6. | पृष्ठ ११.३४

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