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Question
If `bara=3hati-hatj+4hatk, barb=2hati+3hatj-hatk, barc=-5hati+2hatj+3hatk` then `bara.(barbxxbarc)=`
(A) 100
(B) 101
(C) 110
(D) 109
Solution
(C) 110
`bara.(barbxxbarc)=|[3,-1,4],[2,3,-1],[-5,2,3]|`
`=3(9+2)+1(6-5)+4(4+15)`
`=33+1+76`
`=110`
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