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प्रश्न
If sec A = cosec A and 0° ∠A ∠90°, state the value of A
उत्तर
sec A = cosec A
cos A = sin A
cos2A = sin2A
cos2 A = 1 – cos2A
2cos2A = 1
cos A = `(1)/(sqrt2)`
A = 45°
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