What is the cross product of $<-2, 5 ,-2 >$ and $<-1, -9 ,2 >$ ?

Question

1200 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-11-18T17:30:30

$< -2, 5, -2 > xx < -1, - 9, 2 > = <-8, 6, 23 >$

$< -2, 5, -2 > xx < -1, - 9, 2 > =$

$| (hati, hatj, hatk, hati, hatj), (-2, 5, -2, -2, 5), (-1, -9, 2, -1, -9) | =$

${(5)(2) - (-2)(-9)}hati + {(-2)(-1) - (-2)(2)}hatj + {(-2)(-9) - (5)(-1)}hatk =$

$-8hati + 6hatj + 23hatk = <-8, 6, 23 >$

What is the cross product of <-2, 5 ,-2 ><-2, 5 ,-2 > and <-1, -9 ,2 ><-1, -9 ,2 >?