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If a=b cos((2pi)/3)= c cos((4pi)/3), the...

If `a=b cos((2pi)/3)= c cos((4pi)/3),` then write the value of `a b+b c+c a`

A

`-1`

B

0

C

1

D

2

Text Solution

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The correct Answer is:
B
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OBJECTIVE RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS AND IDENTITIES-Exercise
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