If xcostheta=ycos(theta+120^(@))=z cos (...

If `xcostheta=ycos(theta+120^(@))=z cos (theta+240^(@))` then `xy+yz+zx=`

A

`-1`

B

1

C

0

D

`3//4`

Text Solution

Verified by Experts

The correct Answer is:

C

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