find the projection of the vector `hati+3hatj=7hatk` on the vector `7hati-hatj+8 hatk`

Explanation

Let `veca=hati+3hatj+7hatj+7hatkand vecb=7hatj-hatj+8hatk`
Now, projection of vector `veca on vecb` is given by
`1/(|vecb|)(veca.vecb)=1/(sqrt(7^(2)+(-1)^(2)+8^(2))){(7)+3(-1)+7(8)}`
`(7-3=56)/(sqrt(49+1+64))=60/(sqrt114)`