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प्रश्न
Evaluate the following:
cosec3 30° cos 60° tan3 45° sin2 90° sec2 45° cot 30°
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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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