Question

If `bara =3 hati - 2hatj +7 hatk, barb = 5hati + hat j -2 hatk and barc = hati + hatj - hat k, " then find "bara * (barb xx barc)`.

Answer 1

Here `bara = 3 hati - 2 hatj + 7 hatk , barb = 5hati + hatj - 2hatk, barc = hati+ hatj - hatk`
`:. bara * (barbxxbarc)=|(3,-2,7),(5,1,-2),(1,1,-1)|`
` = 3 (-1+2)+2(-5+2)+7(5-1)`
`= 3 (1) + 2 (-3)+7(4)`
` = 3 - 6 + 28`
` :. " " bara*(barb xx barc) = 25.`