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प्रश्न
In ∆ABC, AB = `6sqrt(3)` cm, AC = 12 cm, and BC = 6 cm then m∠A = ?
विकल्प
30°
60°
90°
45°
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उत्तर
30°
Explanation:
We know that, `6 = 1/2(12)`
And `6sqrt(3) = sqrt(3)/2 (12)`
∴ `BC = 1/2 AC` and `AB = sqrt(3)/2 AC`
∴ ∠A = 30° ...(Converse of 30° - 60° - 90° theorem)
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