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Determinant Calculator

determinant calculator. Get instant, accurate results. Enter values for instant results with step-by-step formulas.

Reviewed by Manoj Kumar, Mathematics Educator

Reviewed by Manoj Kumar, Mathematics Educator

Formula

2x2: det = ad - bc | 3x3: det = a(ei-fh) - b(di-fg) + c(dh-eg)

The determinant is a scalar value computed from a square matrix. For 2x2: ad-bc. For 3x3: cofactor expansion along the first row. Determinant = 0 means the matrix is singular (no inverse, zero volume).

Worked Examples

Example 1: 2x2 matrix

Problem:|1 2; 3 4|

Solution:det = (1)(4) - (2)(3) = 4 - 6 = -2

Result:det = -2

Example 2: 3x3 matrix with a zero determinant (singular)

Problem:|1 2 3; 4 5 6; 7 8 9|

Solution:det = 1(5ร—9-6ร—8) - 2(4ร—9-6ร—7) + 3(4ร—8-5ร—7) = 1(45-48) - 2(36-42) + 3(32-35) = -3 + 12 - 9 = 0

Result:det = 0 (singular matrix, no inverse โ€” rows are linearly dependent)

References

Reviewed by Manoj Kumar, Mathematics Educator ยท Editorial policy