Linear Algebra Study Notes

\(A\ =\ (v_1,\ v_2,\ v_3,\ ...,\ v_n),\ x\ =\ (x_1,\ x_2,\ x_3,\ ...,\ x_n)^T\)，\(Ax\ =\ x_1v_1\ +\ x_2v_2\ +\ x_3v_3\ +\ ...\ +\ x_nv_n\)