B+A+D=2 E+2D+C-B+3A=-1 从而得方程组 3C+2E-4D-3B+A=4 3C-4E-8D+4B=9 4A-2C-4B-8E=-10 解此方程组得:A=1B=2C=1D=1E 从而: 2x+-x3+4x2+9x-10 X 5453-2x+4x dx Dax x-2x+2(x+2)2x2-x+1 2x-1 =n|x-2|+2lnx+2|+ In(x-x+I+-rarctg x+2 =hx-2|(x+2) X g +c √x2-x+1 x+2 √37 解此方程组得: A =1 B =2 C =-1 D =-1 E =1 从而得方程组: 从而: