यदि `vec(a)=4hati+3hatj+2hatk` तथा `vec(b)=3hati+2hatk,|vec(b)xx2vec(a)|` निकालें |

Explanation

दिया है, `vec(a)=4hati+3hatj+2hatk` तथा `vec(b)=3hati+2hatk`
`:." "vec(b)=3hati+2hatk` तथा `2vec(a)=8hati+6hatj+4hatk`.
अब, `vec(b)xx2vec(a)=|{:(hati,,hatj,,hatk),(3,,0,,2),(8,,6,,4):}|=(0-12)hati+(16-12)hatj+(18-0)hatk`
`=-12hati+4hatj+18hatk`
`:." "|vec(b)xx2vec(a)|=|-12hati+4hatj+18hatk|`
`=sqrt((-12)^(2)+4^(2)+(18)^(2))=sqrt(484)=22`.
अत:, `|vec(b)xx2vec(a)|=22`.