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State true or false for the following: The complex number cosθ + isinθ can be zero for some θ. - Mathematics

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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

MCQ
True or False

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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Chapter 5: Complex Numbers and Quadratic Equations - Solved Examples [Page 85]

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NCERT Exemplar Mathematics [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Solved Examples | Q 17.(ii) | Page 85

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