Question

If A ⊂ B, then A ∩ B = A ∪ B.



always

sometimes

never

Answer 1

HI!!

Answer 2

sometimes

Answer 3

it is not always true for sure, but it could be true if for example A+B

Answer 4

oops i meant it could be true if \(A=B\)

Answer 5

think of B = {1, 2, 3, ,4 ,5}
and A = {1, 3, 5}
Clearly A is a subset of B
A intersect B = {1,3,5}
A unioned B = {1,2,3,4,5}

Answer 6

in this case the A n B =/= A u B.. This only occurs like when @misty1212 said, when A is a subset of B and B is a subset of A i.e. A = B