# Linear Algebra Conditions

Algebra

### Linear Algebra Conditions

http://imgur.com/a/xIydC
The answers is b) ab≠1, but I have no clue how to get to that answer... Can someone help me?

Guest

### Re: Linear Algebra Conditions

Well as http://domyhomeworkfor.me/ solved it this can easily be done with determinants. If a square matrix's determinant does not equal zero, then that square matrix will have an inverse hence having a unique solution. Since this is a 2x2 matrix, just compute the determinant with the condition that it cannot equal zero:
(1)(2)-(2ab) =/= 0
2 =/= 2ab
1=/= ab

Guest