Joystar77,
please do not post any problems until you have shown attempts in a thread and/or questions
about the problems. Please read these rules for posting:
http://www.freemathhelp.com/forum/th...Before-Posting!!
Do you know what that "little symbol" means? If not, then you need more help than we can here provide. If so, then please reply showing your thoughts and efforts so far. Thank you!Let X, Y be sets. Use set identities to prove that
X (the little symbol that is an upside down U) Y = Y - (Y - X)