Question

What is the cross product of `(4 i + 4 j + 2 k)` and `(- 4 i - 5 j + 2 k)`?

Answer 1

`A X B=18i-16j`

Explanation:

`A=(x,y,z)`
`B=(a,b,c)`
`A X B=i(y*c-z*b)-j(x*c-z*a)+k(x*b-y*a)`
`A=4i+4j+2k`
`B=-4i-5j+2k`
`A X B=i(8+10)-j(8+8)+k(-20+20)`
`A X B=18i-16j+0`
`A X B=18i-16j`