JEE MATHEMATICS MCQ: COMPLEX NUMBERS

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Application +4 | -1

\alpha

and

\beta

are the roots of

x^2-2 x+2=0

, then

\alpha^n+\beta^n=

View answer and explanation

Correct option: B

2^{\frac{n}{2}+1} \cos \frac{n \pi}{4}

Option B,

2^{\frac{n}{2}+1} \cos \frac{n \pi}{4}

, is correct because it is the simplified form of the expression

\alpha^n + \beta^n

where

\alpha

and

\beta

are the roots of the given quadratic equation.

More Questions from COMPLEX NUMBERS

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