According to the definition of algebraic cofactor and determinant expansion, solve it.

explain

1, 2A4 1+2A42+2A43+A44+A45, according to the algebraic cofactor and determinant expansion, is the algebraic cofactor of the second row element multiplied by the fourth row element of the original determinant, so the result is 0.

2.a 4 1+A42+A43 = a 4 1+A42+A43+0×A44+0×A45。 According to the algebraic cofactor and determinant expansion, the fourth row element of the original determinant is changed to 1, 1, 65438.

Computational determinant

1 2 3 4 5

2 2 2 1 1

3 1 2 3 5

1 1 1 0 0

4 3 1 5 0

The result is 5.

Newman Hero 2065438+March 9, 2005 1 1:26:43

I hope it will help you and be adopted.