- #1

kala

- 21

- 0

< M

_{2}(

**R**), usual multiplication > with <

**R**, usual multiplication> where [tex]\varphi[/tex](A) is the determinant of matrix A.

The determinant of the matrix is ad-bc, so [tex]\varphi[/tex](A)=ad-bc.

For this to be an isomorphism, I have to show that the function is one to one, onto and preserves the operations.

I'm having trouble getting this to work. Any suggestions?