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प्रश्न
Without using trigonometric table , evaluate :
`(sin49^circ/sin41^circ)^2 + (cos41^circ/sin49^circ)^2`
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उत्तर
`(sin49^circ/sin41^circ)^2 + (cos41^circ/sin49^circ)^2`
⇒ `(sin(90^circ - 41^circ)/sin41^circ)^2 + (cos(90^circ - 49^circ)/sin49^circ)^2`
⇒ `(cos41^circ/sin41^circ)^2 + (sin49^circ/sin49^circ)^2`
⇒ 1 + 1 = 2
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