JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

1 of 1

Application +4 | -1

z_k=\cos \left(\frac{k \pi}{10}\right)+i \sin \left(\frac{k \pi}{10}\right)

, then

z_1 z_2 z_3 z_4

is equal to

View answer and explanation

Correct option: A

-1

Option A (-1) is correct because by De Moivre's theorem, the product simplifies to

\cos(\pi) + i \sin(\pi)

, which equals -1.

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