JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

1 of 1

Application +4 | -1

z = r(\cos \theta + i\sin \theta )

, then the value of

\frac{z}{{\bar z}} + \frac{{\bar z}}{z}

View answer and explanation

Correct option: B

2\cos 2\theta

Option B (

2\cos 2\theta

) is correct because it is the simplified form of the given expression after substituting

z = r(\cos \theta + i\sin \theta )

and using Euler's formula.

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