Final answer:
None of the provided matrices A and B are invertible as both have a zero determinant. The determinants of matrices C and D cannot be calculated without further information, hence their invertibility is unknown.
Step-by-step explanation:
To determine which matrices are invertible, we need to check if they have a non-zero determinant. A matrix is invertible if its determinant is not equal to zero, which means the matrix has full rank and does not have linearly dependent rows or columns.
- A. [1 2 / 3 6]
- B. [2 -4 8 / 9 -3 12 / 2 -4 8]
- C. [Matrix C]
- D. [Matrix D]
The first matrix A has a determinant of (1*6) - (3*2) = 6 - 6 = 0, so it is not invertible.
The second matrix B can be observed to have two identical rows (first and third rows), which makes its determinant zero, and hence it is not invertible either.
Without additional information, the invertibility of matrices C and D cannot be determined. The question did not provide the specific elements of matrices C and D, so we cannot calculate their determinants.
In conclusion, none of the provided matrices A and B are invertible. Additional information would be necessary to determine the invertibility of matrices C and D.