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Question
sin 2A = 2 sin A is true when A = ______.
Options
0°
30°
45°
60°
Solution
sin 2A = 2 sin A is true when A = 0.
Explanation:
Out of the given alternatives, only A = 0° is correct.
As sin 2A = sin 0° = 0
2 sinA = 2sin 0° = 2(0) = 0
Hence, 0° is correct.
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