y=x+1 代入椭圆方程得:x^2/4+(x+1)^2/2=1x^2+2(x^2+2x+1)=43x^2+4x-2=0x1+x2=-4/3y1+y2=x1+x2+2=-4/3+2=2/3(x1+x2)/2=-2/3,(y1+y2)/2=1/3所以,AB中点M坐标是:(-2/3,1/3)|x1-x2|^2=(x1+x2)^2-4x1x2=(-4/3)^2-4*(-2/3)...