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प्रश्न
If sin x = cos x and x is acute, state the value of x
उत्तर
The angle, x is acute and hence we have, 0 < x
We know that
cos2x + sin2 x = 1
⇒ 2sin2 x = 1
⇒ sin x = `(1)/(sqrt2)`
⇒ x = 45°
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