Mathematics 1228A/B Lecture Notes - Lecture 2: Raffi, Form 10-Q

• School: Western University
• Department: Mathematics
• Course: Mathematics 1228A/B
• Professor: Valluri

Document Summary

Math 1228 lecture 2 techniques of counting continued. Properties of a compliment: (a(cid:1514)b)c = ac(cid:1515)bc, (a(cid:1515)b)c = ac(cid:1514)bc. Define: two sets, a and b, are called mutually exclusive if they have no elements in common they don"t overlap. Define: any collection of sets which are all mutually exclusive and which together include all elements of another set are said to partition that set. = (p(cid:1514)fc(cid:1514)r)c = pc(cid:1515)f(cid:1515)rc: n( ) = 0, n(a(cid:1515)b) = n(a) + n(b) n(a(cid:1514)b) n(a) = n(a(cid:1514)b1) + n(a(cid:1514)b2) + n(a(cid:1514)bk) n(a), the number in set a, counts the elements in set a. N(a) = k, whenever a is a set containing k different elements. Properties of a number in a set: n(ac) = n(u) n(a, partitioning if sets b1,b2, bk partition u, then for any other set a, U = students in class n(u) = 375. Everything grows from the starting point, called the root.