What is the cross product of $[2, 6, -1]$ and $[1, 1, 18]$ ?

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Answer 1 · 2016-11-06T07:47:07

The cross product is $〈109,-37,-4〉$

The cross product of the 2 vectors is given by the determinant

$∣((veci,vecj,veck),(2,6,-1),(1,1,18))∣$

$=veci(108+1)-vecj(36+1)+veck(2-6)$

$109veci-37vecj-4veck$
So the cross product is $〈109,-37,-4〉$

Verifications, the dots products must $=0$

So, $〈109,-37,-4〉.〈2,6,-1〉=218-222+4=0$

$〈109,-37,-4〉.〈1,1,18〉=109-37-72=0$
So the cross product is perpendicular to the two vectors

What is the cross product of [2, 6, -1][2, 6, -1] and [1, 1, 18] [1, 1, 18] ?