Question

已知集A=空集,B={XI（X+1).(X²+3X-4）=0 X∈R}A真包含于C包含于B.求满足条件的集合C

Answer 1

A=ø is subset of any set

A真包含于C => C is a non-empty set

B={x|(x+1).(x²+3x-4）=0 x∈R}

= {x|(x+1)(x+4)(x-1)=0 x∈R}

= {-4,-1,1}

C包含于B => C is a subet of {-4,-1,1}

A真包含于C包含于B => C is a non-empty subset of {-4,-1,1}

{-4},{-1},{1}, {-4,-1},{-4,1},{-1,1}, {-4,-1,1}