It is known that in the triangle ABC, angle B = 45 degrees, angle c = 75 degrees, AC = 2, find BC
Make CD from C and ab perpendicular to d
∠B=45,∠ACB=75
Therefore, a = 60
In RT △ ACD, CD / AC = sin ∠ a = √ 3 / 2
CD / 2 = √ 3 / 2, so CD = √ 3
In RT △ BCD, CD / BC = sin ∠ B = √ 2 / 2
√3/BC=√2/2
√2BC=2√3
BC=√6
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