add 2x2 case check in det()
add 2x2 case check in det()

smarden1/jstat,cmpolis/jstat,NorthDecoder/jstat,smarden1/jstat,akrawitz/jstat,NorthDecoder/jstat,jstat/jstat,JeebsM/jstat,JeebsM/jstat,jstat/jstat,akrawitz/jstat,jamescgibson/jstat,ggonzale/jstat,ggonzale/jstat