Let a be the common cardinality of sets A and C. Let b be the size of B. If C is a subset of B, then a<= b. I understand why this is true, but how do I give a solid proof? Thanks.
Follow Math Help Forum on Facebook and Google+
Originally Posted by jzellt Let a be the common cardinality of sets A and C. Let b be the size of B. If C is a subset of B, then a<= b. I understand why this is true, but how do I give a solid proof? Thanks. note that if , then (you can prove this by contradiction). here, since , we have
View Tag Cloud