Answer
$28i+44j-24k$
Work Step by Step
Let us consider two vectors $v=xi+yj+zk$ and $w=pi+qj+rk$. Then the cross product of the two vectors $v$ and $w$ can be computed in the form of the determinant as:
$ v \times w=\begin{vmatrix}
i & j & k \\
x & y & z \\
p & q & r \\ \end{vmatrix}$
We have:
$det =v \times 4w =[(3)(12)-(2)(4)] i -j [(-3)(12) - (2)(4)]+k [(-3)(4) -(3) (4)]=28i+44j-24k$
