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Question
`(1 - tan^2 45^circ)/(1 + tan^2 45^circ)` = ?
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Solution
`(1 - tan^2 45^circ)/(1 + tan^2 45^circ) = (1 - (1)^2)/(1 + (1)^2)` ...[∵ tan 45° = 1]
= `(1 - 1)/(1 + 1)`
= `0/2`
= 0
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