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Question
Evaluate the following:
`(sin 20^@)/(cos 70^@)`
Solution
Given that `(sin 20^@)/(cos 70^@)`
Since `sin(90 - theta) = cos theta`
`=> (sin 20)/(cos 70) = (sin(90 - 70))/cos 70`
`=> sin 20/cos 70 = cos 70/cos 70`
`=> sin 20/ cos 70 = 1`
Therefore `(sin 20^@)/(cos 70^@) = 1`
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