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In a Delta ABC,cos((B+2C+3A)/2)+cos((A-B...

In a `Delta ABC,cos((B+2C+3A)/2)+cos((A-B)/2)=`

A

-1

B

0

C

1

D

2

Text Solution

Verified by Experts

The correct Answer is:
B
ln `a DeltaABC`
`A+B+C=pi`
`therefore cos((B+2C+3A)/(2))+cos((A-B)/(2))`
`=2cos((2C+4A)/(4))cos((2A+2B+2C)/(4))`
`=2cos((C+2A)/(2))cos((pi)/(2))=0`
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MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-FACTORIZATION FORMULAE -EXERCISE 2
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