Current location - Training Enrollment Network - Mathematics courses - Given sets a = {- 1, 2, 2, 4} and b = {- 1, 2}, then A∩B=? This is called Jiangsu 20 1 1 Mathematics College Entrance Examination. Is this question okay?
Given sets a = {- 1, 2, 2, 4} and b = {- 1, 2}, then A∩B=? This is called Jiangsu 20 1 1 Mathematics College Entrance Examination. Is this question okay?
A∩B={- 1，2}
There is an axiom in set theory called zermelo-fraenkel, which says that two sets A and B composed of objects satisfy.