Determinant of Matrix

Question

Expand by minors on the row or column that appears to make the computation easiest.

 

[-3, 0, 0; 7, 11, 0; 1, 2, 2] (so semicolon means end of row)

Answer 1

Vanessa,

 

Row 1 and Column 3 both have two zeros, so these would make the computation fastest.

 

Using Row 1 with A being the given matrix,

 

det A = -3 (-1)¹⁺¹ M₁₁ = -3 det [11,0; 2,2] = -3(22) = -66.

 

If you use Column 3 you will (of course get the same answer).