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प्रश्न
In ΔABC, a = 3, b = 4 and sin A = `3/4`, find ∠B
उत्तर
By sine rule,
`"a"/(sin "A") = "b"/(sin "B")`
∴ `3/(3/4) = 4/(sin "B")`
∴ sin B = 1 = `sin pi/2`
∴ ∠B = `pi/2`
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