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Question
Evaluate
`(sin ^2 63^@ + sin^2 27^@)/(cos^2 17^@+cos^2 73^@)`
Solution
`(sin ^2 63^@ + sin^2 27^@)/(cos^2 17^@+cos^@73^@)`
`(= [sin(90^@ - 27^@)]^2+sin^2 27^@)/([cos(90^@ - 73^@)]^2 + cos^2 73^@)`
`= ([cos27^@]^2 + sin^2 27^@)/([sin 73^@]^2 + cos^2 73^@)`
`= (cos^2 27^@ + sin^2 27^@)/(sin^2 73^@+ cos^2 73^@)`
= 1/1 (As sin2A + cos2A = 1)
= 1
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