Question

设集合A={-4,m^2},B={m-5,1-m},又A∩B={-4},

Answer 1

A={-4,m^2}

B={m-5,1-m}

A∩B={-4}

case 1:m-5 =-4 ie m=1

m^2 = 1

1-m = 1-1 =0

accept case 1

case 2:1-m =-4 ie m= 5

m^2=25

m-5= 0

accept case 2

ie m=1 or m=5