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प्रश्न
Find acute angles A & B, if sin (A + 2B) = `sqrt3/2 cos(A + 4B) = 0, A > B`
उत्तर
Sin (A + 2B) = Sin 60°
Cos (A + 4B) = cos 90°
A + 2B = 60° …(i)
A + 4B = 90° …(ii)
Subtracting (ii) from (i)
A + 4B = 90°
`(−A – 2B = −60)/(2B = 30°)` ∴ B = 15°
A + 4B = 90°
4B = 4(15°) = 4B = 60°
∴ A + 60° = 90° ∴ A = 30°
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