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प्रश्न
Given that sinα = `1/2` and cosβ = `1/2`, then the value of (α + β) is ______.
पर्याय
0°
30°
60°
90°
उत्तर
Given that sinα = `1/2` and cosβ = `1/2`, then the value of (α + β) is 90°.
Explanation:
Given,
sinα = `1/2` = sin30° ...`[∵ sin 30^circ = 1/2]`
⇒ α = 30°
And cosβ = `1/2` = cos60° ...`[∵ 60^circ = 1/2]`
⇒ β = 60°
∴ α + β = 30° + 60° = 90°
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