page1
A
B
a,b
a
b
a,b
a,b
a
M:
C
D
a,b
a,b
b
Mα:
{A,C}
{A,C,B}
{A,C,D}
{A,C,D,B}
a,b
a
a
a
b
b
b
M':
A
a,b
b
Mc:
K
{K,C}
{C}
{C,D}
{K,C,D}
a,b
a
a
a
b
b
b
Mc∩Mα
{A}
{A,B}
a
M:
b
a,b
b
b