江西省萍鄉(xiāng)二中高中數(shù)學(xué) 131集合的基本運(yùn)算課件 北師大版必修1

1、新課,示例,1,觀察下列三個(gè)集合,A,1,3,5,C,1,2,3,4,5,6,B,2,4,6,集合,C,是由集合,A,或?qū)儆诩?B,的,元素組成的，稱,C,是,A,與,B,的,并集,1,并,集,定義,由所有屬于集合,A,或,B,的元素組成,的集合，稱為,集合,A,與集合,B,的并集,記作,A,B,即,A,B,x,x,A,或,x,B,用,Venn,圖表示為,A,B,例,1,設(shè)集合,A,4,5,6,8,集合,B,3,5,7,8,9,求,A,B,解,A,B,3,4,5,6,7,8,9,例,2,設(shè)集合,A,x,1,x,2,集合,B,x, 1,x,3,求,A,B,解,A,B,x,1,x,3,x,1,1

2、,2,3,分析,練,1,設(shè)集合,A,x,1,x,2,集合,B,x, 1,x,3,求,A,B,解,A,B,x,1,x,3,x,1,1,2,3,分析,練,2,設(shè)集合,A,x,1,x,2,集合,B,x,x,2,求,A,B,解,A,B,x,x,1,x,1,2,分析,A,A,A,A,B,性質(zhì),A,A,B,A,A A,B,B A,B,示例,2,考察下列各集合,A,4,3,5,B,2,4,6,C,4,2,交,集,集合,C,的元素既屬于,A,又屬于,B,稱,C,為,A,與,B,的,交集,2,交,集,定義,由既屬于集合,A,又屬于集合,B,的所,有元素組成的集合，叫作,A,與,B,的交集,記作,A,B,C,x,

3、x,A,且,x,B,讀作,A,交,B,用,Venn,圖表示為,A,B,例,3,A,2,4,6,8,10,B,3,5,8,12,C,6,8,求,A,B,A,B,C,A,x,x,是某班參加百米賽的同學(xué),B,x,x,是某班參加跳高的同學(xué),求,A,B,8,8,8,A,B,x,x,是某班參加百米賽且參加跳高的同學(xué),例,4,設(shè)集合,A,y,y,x,2,x,R,B,x,y,y,x,2,x,R,則,A,B,A.,1, 1,2, 4) B.,1, 1,C (2, 4) D,D,例,5,設(shè)集合,A,x,1,x,2,集合,B,x, 1,x,3,求,A,B,解,A,B,x,1,x,2,x,1,1,2,3,分析,練,3

4、,設(shè)集合,A,x,1,x,2,集合,B,x, 1,x,3,求,A,B,解,A,B,x,1,x,2,x,1,1,2,3,分析,練,4,設(shè)集合,A,x,1,x,2,集合,B,x,x,2,求,A,B,x,1,2,分析,練,4,設(shè)集合,A,x,1,x,2,集合,B,x,x,2,求,A,B,解,A,B,x,1,2,分析,A,B,x,x,A,且,x,B,性質(zhì),AB A,AB A,A,B B,A,A,A,B,A,例,6,已知集合,A,x,x,是不大于,10,的正,集合,B,x,x,是,12,的正,求,A,B,AB,約數(shù),解,1,2,3,4,6,12,B,1,2,3,4,5,6,7,9,12,A,B,U,1,3,5,7,9,A,1,3,A,B,I,奇數(shù),思考交流,下列結(jié)論成立嗎,1).(A,B,C=A,B,C,2).(AB)C=A(BC,課堂小結(jié),A,B,x,x,A,或,x,B,A,B,x,x,A,且,x,B,A,A,A,A,A,A,A,A,A,A,B,B,A,A,B,B,A,1,交集，