1.(2a+b)x+(a+b)y+a-b=0得a(2x+y+1)+b(x+y-1)=0,所以2x+y+1=0且x+y-1=0,所以x= -2,y=3,所以这个定点为(-2,3)
2.由题意得:-2m^2+6-n^2=0得m^2/3+n^2/6=1,所以c^2=6-3=3,c=根号3,焦点坐标为(0,根号3)和(0,-根号3)
1.(2a+b)x+(a+b)y+a-b=0得a(2x+y+1)+b(x+y-1)=0,所以2x+y+1=0且x+y-1=0,所以x= -2,y=3,所以这个定点为(-2,3)
2.由题意得:-2m^2+6-n^2=0得m^2/3+n^2/6=1,所以c^2=6-3=3,c=根号3,焦点坐标为(0,根号3)和(0,-根号3)