If A = B = 45°, show that :
(i) sin(A - B) = sin A cos B - cos A sin B
(ii) cos(A + B) = cosA cosB - sin A sin B
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If A = 45°, verify that :
(i) sin 2A = 2 sin A cos A
(ii) cos 2A = (2 cos2A - 1) = (1 - 2 sin2A)
If A = 60° and B = 30°, show that :
(sin A cos B + cos A sin B)2 + (cos A cos B - sin A sin B)2 = 1