Question

3sin52°30×sin7°30
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Answer 1

sin(a)*sin(b) = 1/2(cos(a-b) - cos(a+b))
3*(1/2(cos45- cos60))= 3* (1/2(√2/2 - 1/2))= 1,5(√2/2-1/2)= ((√2-1)*3)/4 = (3√2-3)/4