हिंदी

The value of the expression [sin222∘+sin268∘cos222∘+cos268∘+sin263∘+cos63∘sin27∘] is ______. - Mathematics

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प्रश्न

The value of the expression `[(sin^2 22^circ + sin^2 68^circ)/(cos^2 22^circ + cos^2 68^circ) + sin^2 63^circ + cos 63^circ sin 27^circ]` is ______.

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MCQ
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उत्तर

The value of the expression `[(sin^2 22^circ + sin^2 68^circ)/(cos^2 22^circ + cos^2 68^circ) + sin^2 63^circ + cos 63^circ sin 27^circ]` is 2.

Explanation:

Given expression,

`(sin^2 22^circ + sin^2 68^circ)/(cos^2 22^circ + cos^2 68^circ) + sin^2 63^circ + cos 63^circ sin 27^circ`

= `(sin^2 22^circ + sin^2(90^circ - 22^circ))/(cos^2(90^circ - 68^circ) + cos^2 68^circ) + sin^2 63^circ + cos 63^circ sin(90^circ - 63^circ)`

= `(sin^2 22^circ + cos^2 22^circ)/(sin^2 68^circ + cos^2 68^circ) + sin^2 63^circ + cos 63^circ * cos 63^circ`   ...`[(∵ sin(90^circ - theta) = cos theta),("and" cos(90^circ - theta) = sin theta)]`

= `1/1 + (sin^2 63^circ + cos^2 63^circ)`  ...[∵ sin2θ + cos2θ = 1]

= 1 + 1

= 2

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अध्याय 8: Introduction To Trigonometry and Its Applications - Exercise 8.1 [पृष्ठ ९१]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 10
अध्याय 8 Introduction To Trigonometry and Its Applications
Exercise 8.1 | Q 11 | पृष्ठ ९१

वीडियो ट्यूटोरियलVIEW ALL [2]

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