解:有题意可知,AB的中点在直线y=x+m上,且直线AB的斜率为-1,则y1=x1^2y2=x2^2x1*x2=-1(y1+y2)/2=(x1+x2)/2+m(y1-y2)/(x1-x2)=-1所以(y1-y2)/(x1-x2)=(x1^2-x2^2)/(x1-x2)=(x1+x2)=-1(y1+y2)/2=(x1+x2)/2+m,即x1^2+x2^2=x1+x2+2m(x1+x2)^2-2x1x2=x1+x2+2m即1-2*(-1/2)=-1+2m所以m=3/2