A. B.π C. D.
A.a2-2a-2b-3=02 B.a2+2a+2b+5=0 C.a2+2b2+2a+2b+1=0 D.3a2+2b2+2a+2b+1=02
A.4 B.3 C.4 D.8
A.1 B.4 C.1或3 D.1或4
A.相交且过圆心 B.相切 C.相离 D.相交但不过圆心