# Math Help - Discrete mathematics set theory problem!

1. ## Discrete mathematics set theory problem!

I got a question that myself cant solve hope anyone here maybe could help!

"Explain why the arbitrary amounts of M1, M2, M3, M4 must always apply to (M1 U M3) \ (M2 U M4) C (M1 \ M2) U (M3 \ M4) "

// Winy

2. Hi Winy,
I'm not sure exactly about your problem, but it looks like something I'd try and draw a Venn diagram of first up? Could that help?

3. Originally Posted by Winy
"Explain why the arbitrary amounts of M1, M2, M3, M4 must always apply to (M1 U M3) \ (M2 U M4) C (M1 \ M2) U (M3 \ M4) "
Notice that $x \notin \left( {M_2 \cup M_4 } \right)\;\Rightarrow \quad x \notin {\rm M}_2 \wedge x \notin {\rm M}_4$
Also $x \in M_1 \wedge x \notin M_2 \wedge x \notin M_4 \Rightarrow \quad x \in \left( {M_1 \backslash M_2 } \right)$

4. Thanks alot for your help and fast replays ! Hopefully i can figure it out now