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Evaluate the following: cosec^3 30° cos 60° tan^3 45° sin^2 90° sec^2 45° cot 30°

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प्रश्न

Evaluate the following:

cosec3 30° cos 60° tan3 45° sin2 90° sec2 45° cot 30°

मूल्यांकन
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उत्तर

cosec3 30° cos 60° tan3 45° sin2 90° sec2 45° cot 30°............(i)

By trigonometric ratios, we have

`cosec 30^@ = 2, cos 60^@ = 1/2, tan 45^@ = 1     sin 90^@ = 1  sec 45^@ = sqrt2   cot 30^@ = sqrt3`

By substituting above values in (i), we get

`[2]^3 . 1/2 . (1)^3 . (1)^2 (sqrt2). sqrt3`

`=> 8. 1/2 . 1. 2 . sqrt3 => 8sqrt3`

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अध्याय 10: Trigonometric Ratios - EXERCISE 10.2 [पृष्ठ १०.२९]

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आर.डी. शर्मा Mathematics [English] Class 10
अध्याय 10 Trigonometric Ratios
EXERCISE 10.2 | Q 6. | पृष्ठ १०.२९

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