Question

Answer 1

Bài 2: X={1/x|x=k(k+1);k∈N*; 1<=k<=5}

Bài 1: A={x∈R|-3<x<7}

=>A=(-3;7)

B={x∈R|x>2}

=>B=(2;+∞)

A\(\cap\) B=(-3;7)\(\cap\) (2;+∞)

=(2;7)

A\(\cup\) B=(-3;7)\(\cup\) (2;+∞)

=(-3;+∞)

A\B=(-3;7)\(2;+∞)

=(-3;2]

\(C_{R}B\) =R\B=R\(2;+∞)

=(-∞;2]