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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
A = 600 and B = 300
Now, A + B = 600 + 300 = 900
Also, A – B = 600 – 300 = 300
(i) sin (A + B) = sin 900 = 1
sin A cos B + cos A sin B = sin 600 cos 300 + cos 600 sin 300
=`(sqrt(3)/2xx sqrt(3)/2 + 1/2xx1/2) = (3/4+1/4)=1`
∴ sin (A + B) = sin A cos B + cos A sin B
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