6.4. EXERCISES 121
(c)
1 2 3 21 3 2 34 1 5 01 2 1 2
, ( −2.)
2. Find the following determinant by expanding along the first row and second column.
det
1 2 12 1 32 1 1
3. Find the following determinant by expanding along the first column and third row.
det
1 2 11 0 12 1 1
4. Find the following determinant by expanding along the second row and first column.
det
1 2 12 1 32 1 1
5. Compute the determinant by cofactor expansion. Pick the easiest row or column to
use.
det
1 0 0 12 1 1 00 0 0 22 1 3 1
6. Find the determinant using row operations.
det
1 2 12 3 2−4 1 2
7. Find the determinant using row operations.
det
2 1 32 4 21 4 −5
8. Find the determinant using row operations.
det
1 2 1 23 1 −2 3−1 0 3 12 3 2 −2