Question

ex 4 plz va dau coroana

Answer 1

A∪B={1,2,3,4,7}
B∩C={1,2,4,}
A=B1,2,3}
B={1,4,7,a}       a=2
C={2,3,b,8,4}    b=1

Answer 2

A={1,2,3}
B={1,4,7,2}
a=2
A∪B={1,2,3,4,7}
C={2,3,1,8,4}
b=1
B∩C={1,2,4}