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The position vectors of vertices of a De...

The position vectors of vertices of a `Delta ABC` are `4hat(i)-2hat(j), hat(i)-3hat(k)` and `-hat(i)+5hat(j)+hat(k)` respectively, then `angle ABC` is equal to

A

`pi/6`

B

`pi/4`

C

`pi/3`

D

`pi/2`

Text Solution

Verified by Experts

The correct Answer is:
D
Here, `AB=-3 hati+6hatj-3hatk`
`BC = -2 hati+hatj+4hatk`
and `AB*BC=6+6-12=0`
`rArr" "/_ABC=pi/2`
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MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-VECTORS -( MHT CET Corner)
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