(cardinalul unei multimi reprezinta cate numere sunt in multime. ex: ai A={1,2,3} cardA=3 (pt ca sunt 3 nr) )
A U B ={-5,-4,-3,-2,-1,0,1,2,3,4,5,6}
card A U B = 12
A U invers B =o taiat (multime vida)
card de A U invers B= 0
sper ca nu am gresit la calcule :))
sper ca ai inteles :)