1)

2)

3)

ถูกทุกข้อ

( A ∩ B ) ∩ C

B∪( A ∩ C )

( A ∩ B ) ∪ C

( B ∩ C ) ∪ A

( A ∩ B ) ∩ C

( A ∩ C ) ∪ B

( A ∩ B ) ∪ C

( B ∩ C ) ∪ A

( A ∩ B ) – (A ∩ C )

( A ∩ C ) - B

( A - B ) ∪ (A - C )

B - C ) ∪ (A - C )

B = {e,f}

B = {3,4,e,f}

A = {1,2,3,4,a,b}

A = {1,2,3,4,a,b,c,d}

A - B = {1,2,3,4}

A - B = {1,2,3,4,a,b}

A - B = {1,2,3,4,a,b,c,d}

A - B = {1,2,a,b}

A ∩ B = {3,4,c,d}

A ∩ B = {1,2,3,4,a,b}

A ∩ B = {1,2,3,4,a,b,c,d}

A ∩ B = {1,2,a,b}

(A ∪ B ′) = {1,2,3,4,c,d}

(A ∪ B ′) = {1,2,a,b }

(A ∪ B ′) = {1,2,3,4,a,b,c,d,e,f}

(A ∪ B ′) = {1,2,a,b,c,d,e,f}

(B ∪ A ′) = {1,2,3,4,c,d}

(B ∪ A ′) = {1,2,a,b }

(B ∪ A ′) = {1,2,3,4,a,b,c,d,e,f}

(B ∪ A ′) = {e,f}