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Question
State true or false for the following:
The complex number cosθ + isinθ can be zero for some θ.
Options
True
False
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Solution
This statement is False.
Explanation:
Because cosθ + isinθ = 0
⇒ cosθ = 0 and sinθ = 0.
But there is no value of θ for which cosθ and sinθ both are zero.
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