JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

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Analyzing +4 | -1

The value of

\sum\limits_{{k=1}}^{n-1}(n-k) \cos \frac{2 k \pi}{n} \quad(n \geq 3

is an integer)

View answer and explanation

Correct option: A

-\frac{n}{2}

Option A (-n/2) is correct because the sum can be simplified using trigonometric series identities.

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