Consider the system Ax=bAx = bAx=b where AAA is 3×33 \times 33×3 and det(A)=0\det(A) = 0det(A)=0. Which statement is ALWAYS true?
Cramer's rule can be applied to find the unique solution.
The system has either infinitely many solutions or no solution.
The matrix AAA is invertible.
The determinant of ATA^TAT equals 111.