A={X/X+4X=0}={0,-4}B={X/X^2+2(a+1)X+a-1=0}1)x=0a-1=0a=12)x=-416+2(a+1)(-4)+a-1=0-8a+7+a=0a=13)x=0 x=-4X^2+2(a+1)X+a-1=00(-4)=a-1a=10-4=-2(a+1)a=1∴a=1