答案:取(p1,p2,p3)为初始基,对应基解x(0)=(-5,1,8,0,0,0)T,x(0)非可行解,目标函数的非基变量表达式为f=-2+2x4-6x6.由检验数λ6=6>0可知,x(0)也非正则解.增加人工约束:x4+x5+x6+x7=M求解对应扩充问题,列出扩充问题的初始单纯形表,如表3-25.首次迭代得表3-26.然后进行两次对偶单纯形迭代,依次得表3-27和表3-28.表3-25x4x5x6f-2-206x1x2x3x7-518M1-37-11-131-10111*表3-26x4x5x7f-6M-2-8-6-6x1x2x3x6-7M-5M+110M+8M-6-10*-7021131110111表3-28对应的基解是扩充问题的最优解,但对应目标函数值与M有关.由此可知原问题的目标函数在可行域上无下界,因此无最优解表3-27x4x1x7f-frac{9}{5}M+1-frac{22}{5}-frac{3}{5}-frac{9}{5}x5x2x3x6frac{7}{10}M+frac{1}{2}-frac{2}{5}Mfrac{23}{10}M+frac{5}{2}frac{3}{10}M-frac{1}{2}frac{3}{5}-frac{1}{10}frac{7}{10}-frac{6}{5}^{*}frac{1}{5}-frac{2}{5}frac{32}{5}frac{11}{10}frac{23}{10}frac{2}{5}frac{1}{10}frac{3}{10}表3-28x2x1x7f-frac{1}{3}M+1-frac{11}{3}-frac{4}{3}-frac{1}{3}x5x4x3x6frac{1}{2}M+frac{1}{2}frac{1}{3}Mfrac{1}{6}M+frac{5}{2}frac{1}{6}M-frac{1}{2}frac{1}{2}0frac{1}{2}-frac{5}{6}-frac{1}{6}frac{1}{3}frac{16}{3}frac{13}{6}frac{1}{6}frac{1}{3}frac{1}{6}frac{1}{6}