Question
If sin(A + B) = sinAcosB + cosAsinB, then the value of
sin75° isSolution
Since, sin(A + B) = sinAcosB + cosAsinB
Let A = 30 o and B = 45 o
sin(30 o + 45 o ) = sin30 o cos45 o + cos30 o sin45 o = 1/2√2 + √3/2√2 = (√3 + 1)/2√2
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