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Question
If A = 600 and B = 300, verify that:
(i) sin (A – B) = sin A cos B – cos A sin B
Solution
sin (A-B)= sin `30^0 = 1/2`
sin A cos B - cos A sin B = sin `60^0 cos 30^0 - cos 60^0 sin 30^0`
=` (sqrt(3)/2 xx sqrt(3)/2 - 1/2 xx1/2 ) =(3/4 - 1/4) = 2/4 =1/2`
∴ sin (A – B) = sin A cos B – cos A sin B
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