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Find `veca.(vecbxxvecc), " if " veca=2hati+hatj+3hatk, vecb=-hati+2hatj+hatk " and " vecc=3hati+hatj+2hatk`

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#### Solution

Here `veca=2hati+hatj+3hatk, vecb=-hati+2hatj+hatk and vecc=3hati+hatj+2hatk`

`veca.(vecbxxvecc)`

`(vecbxxvecc)=|[hati,hatj,hatk],[-1,2,1],[3,1,2]|=3hati+5hatj-7hatk`

Now `veca.(vecbxxvecc)=(2hati+hatj+3hatk)(3hati+5hatj-7hatk)`

`=veca.(vecbxxvecc)=6+ 5−21=−10`

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