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प्रश्न
`(1 - tan^2 45^circ)/(1 + tan^2 45^circ)` = ?
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उत्तर
`(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
संबंधित प्रश्न
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= `square/49`
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Activity:
`square` = 1 + tan2θ ......[Fundamental trigonometric identity]
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Solution :
L.H.S. = cotθ + tanθ
= `cosθ/sinθ + sinθ/cosθ`
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∴ cotθ + tanθ = cosecθ × secθ
