Which of the following equals $\mathbf{A}\times\mathbf{B}$ for $\mathbf{A}=\langle 1,2,0\rangle$ and $\mathbf{B}=\langle 3,-1,4\rangle$?

Using $\mathbf{A}\times\mathbf{B}=\langle A_2B_3-A_3B_2,\ A_3B_1-A_1B_3,\ A_1B_2-A_2B_1\rangle$, we get $\langle 2\cdot 4-0\cdot(-1),\ 0\cdot 3-1\cdot 4,\ 1\cdot(-1)-2\cdot 3\rangle=\langle 8,-4,-7\rangle$. A common mistake is reversing the order, which would change the sign.