1. Note that .
2. Suppose you want to interchange and .
First add to to get .
Next subtract from to get , .
Next add to to get , . Finally multiply by (interchanging two rows or columns changes the sign of the determinant).
1.-Could you please help me to find all solutions to the following system of equations.
2.-Prove that the interchange of two rows of a matrix can be accomplished by a finite sequence of elementary row operations of the other two types.
Thanks a lot