Find each unknown number:4.2 102

Notes Revision 1 ● Subset of a set ○ x3­27/x­3 = (x­9)(x^2+9x) ○ x^3­8/x­2=(x­2)(x^2+4x+2)/(x­2) ● Set under consideration in a problem ○ ex: 2 sets u= {1,2,4,7,9}, a= {2,4,7}, a1= {1,9} ● The complement to set A, when in A1 in the set Abut in U but not in A ● Operations on sets: union of 2 sets A and B, written aB, in the set A as in set B or in both sets A and B ○ ex: A={a,b,c}, B={f,g}, P={a,b,c,f,g,hB={a,b,c,f,g} ○ Intersection of sets A and B. The sets of elements that belong to both A and B. Symbolically then in written asB. ○ ⋃­union, u­universal,­intersection ○ ex: A={1,2,3,5}, B={1,2}, B={1,2} Let A={1,2,4,5