मराठी

Prove the following identities: (1 + tan theta + cot theta)(sin theta – cos theta) = ((sec theta)/(cosec^2 theta) – (cosec theta)/(sec^2 theta))

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प्रश्न

Prove the following identities:

`(1 + tan theta + cot theta)(sin theta - cos theta) = ((sec theta)/("cosec"^2 theta) - ("cosec"  theta)/(sec^2 theta))`

सिद्धांत
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उत्तर

LHS = `(1 + tan theta + cot theta )(sintheta - cos theta) `

= `sin theta + tan theta sin theta + cot theta sin theta - cos theta - tan theta cos theta - cot theta cos theta `

= `sin theta + tan theta sin theta + cos theta/sin theta xx sin theta - cos theta - sin theta/cos theta xx cos theta - cot theta cos theta`

= `sin theta + tan theta  sin theta + cos theta - cos theta - sin theta - cot theta cos theta`

= `tan theta sin theta - cot theta cos theta`

= `sin theta/cos theta xx 1/(cosec theta) - cos theta/sin theta xx 1/sec theta`

= `1/(cosec theta) xx 1/(cosec theta) xx sec theta - 1/sec theta xx 1/sec theta xx cosec theta`

= `sec theta/(cosec^2 theta) - (cosec theta)/sec^2 theta`

= RHS

Hence, LHS = RHS

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पाठ 13: Trigonometric identities - EXERCISE 13A [पृष्ठ ६१८]

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आर. एस. अग्रवाल Mathematics [English] Class 10
पाठ 13 Trigonometric identities
EXERCISE 13A | Q 29. | पृष्ठ ६१८

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