Matrices

Walkthrough

Find the determinant of |1 2 ; 3 4|.

1. 1.Recall the determinant formula for a 2×2 matrix: det = ad − bc, where the matrix is |a b ; c d|.
2. 2.Identify the matrix entries: a = 1, b = 2, c = 3, d = 4.
3. 3.Substitute into the formula: det = (1)(4) − (2)(3).
4. 4.Compute: det = 4 − 6 = −2.
5. 5.So the determinant is −2.