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प्रश्न
Evaluate the following :
`(sin 21^@)/(cos 69^@)`
उत्तर
Given that `(sin 21^@)/(cos 69^@)`
Since `sin (90 - theta) = cos theta`
`=> (sin 21)/(cos 69) = sin(90 - 69)/cos 69`
`=> sin 21/cos 69 = cos 69/cos 69`
`=> sin 21/cos 69 = 1`
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