间题7: 我们说两个线性规划 等价”(equivalent) 是什么意思?
maximize 2x1 3x2 maximize 2x1 -3x2+3x5 subject to subject to x1+ X2 =7 x1+ 3 - =7 L: x1- 2x2 ≤4 → L': x1- 2x2 2x2 ≤4 0. 1:X:X2 ≥0. 问题8: 这两个线性规划是如何等价的?
L: L’:
maximize 2x1-3x2+3x2 subject to x1+3 x2 =7 x1-2x2 2x5 ≤4 X1:X2.X2 ≥ 0. maximize 2x1- 3x2+3x subject to x1+x2 x ≤7 x1+x2 x2 ≥7 x1-2x2 2x3 ≤ 4 X1.x2.x2 乙 0 maximize Cx maximize 2x1-3x2 +3x3 subject to subject to x1+x2 x3≤ 7 + Ax ≤ -x1-x2 X3 b ≤-7 x1-2x2 +2x3 4 ≥ 0 X1,X2,X3 ≥ 0
再回头看看这四种情况下的标准化及 最优解的获得: mizing a linear function subject to linear constraints,into standard form.A linear program might not be in standard form for any of four possible reasons: 1.The objective function might be a minimization rather than a maximization. 2.There might be variables without nonnegativity constraints. 3.There might be eguality constraints,which have an equal sign rather than a less-than-or-equal-to sign. 4.There might be inequality constraints,but instead of having a less-than-or- equal-to sign,they have a greater-than-or-equal-to sign
再回头看看这四种情况下的标准化及 最优解的获得:
问题9: 怎么样就可以将不等式改 写为等式形式? s=b-∑ax ∑ayy≤bi→ i三1 0 我们为什么“无”中生有这个变量? 这个变量为什么取名为松弛变量?
我们为什么“无”中生有这个变量? 这个变量为什么取名为松弛变量?