1.m^2+13m+1=0,m^3+12m^2-12m+2004=?2.已知x=a^2+2a+b^2,y=4b-7,比较x、y的大小

1.m^2+13m+1=0,m^3+12m^2-12m+2004=?2.已知x=a^2+2a+b^2,y=4b-7,比较x、y的大小

m^3+12m^2-12m+2004
=m³+13m²+m-m²-13m+2004
=m(m²+13m+1)-(m²+13m+1)+2005
=0-0+2005
=2005
x-y=a²+2a+b²-4b+7=(a+1)²+(b-2)²+2>0
∴x>y