If $x = y\,\,\cos \,\,\frac{{2\,\pi }}{3} = z\,\,\cos \frac{{4\,\pi }}{3}$, then $xy + yz + zx = $

JEE MATHEMATICS MCQ: MULTIPLE AND SUBMULTIPLE ANGLES

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x = y\,\,\cos \,\,\frac{{2\,\pi }}{3} = z\,\,\cos \frac{{4\,\pi }}{3}

, then

xy + yz + zx =

View answer and explanation

Correct option: B

Option B (0) is correct because when x, y, and z are expressed in terms of a common variable, the expression xy + yz + zx simplifies to 0.

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