JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

1 of 1

Application +4 | -1

x=\cos \theta+i \sin \theta

and

y=\cos \phi+i \sin \phi

, then

x^m y^n+\frac{1}{x^m y^n}=

View answer and explanation

Correct option: C

2 \cos (m \theta+n \phi)

Option C (2

\cos(m\theta + n\phi)

) is correct because by using Euler's formula and simplifying the expression, we arrive at 2

\cos(m\theta + n\phi)

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\alpha, \beta

\gamma

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