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Prove the following: sinθ1+cosθ+1+cosθsinθ = 2cosec - Mathematics

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प्रश्न

Prove the following:

`sintheta/(1 + cos theta) + (1 + cos theta)/sintheta` = 2cosecθ

योग
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उत्तर

L.H.S = `sintheta/(1 + cos theta) + (1 + cos theta)/sintheta`

Taking the L.C.M of the denominators,

We get,

= `(sin^2theta + (1 + cos theta)^2)/((1 + cos theta)* sintheta)`

= `(sin^2theta + 1 + cos^2theta + 2costheta)/((1 + costheta) * sin theta)`

Since, sin2θ + cos2θ = 1

= `(1 + 1 + 2costheta)/((1 + costheta) * sin theta)`

= `(2 + 2 cos theta)/((1 + cos theta) * sin theta)`

= `(2(1 + cos theta))/((1 + cos theta) * sin theta)`

Since, `1/sin theta` = cosec θ

= `2/sin theta`

= 2 cosec θ

R.H.S

Hence proved.

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Introduction To Trigonometry and Its Applications - Exercise 8.3 [पृष्ठ ९५]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 10
अध्याय 8 Introduction To Trigonometry and Its Applications
Exercise 8.3 | Q 1 | पृष्ठ ९५

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