Question

Plz guys answer Qno. 16

Answer 1

$\sin(a - b) = \frac{1}{2} \sin(a - b) = \sin(30) \\ a - b = 30 \: \: \: \: \: \: \: \: \: - 1 \\ \\ similarily \\ \cos(a + b) = \frac{1}{2} \\ \cos(a + b) = \cos(60) \\ a + b = 60 \: \: \: \: - 2 \\ \\ add \: eq.1and \: 2 \\ 2a = 90 \\ a = 45 \\ \\ put \: a \: in \: eq.1 \\ 45 - b = 30 \\ b = 15$
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