x1=1,f(x1)=4;x2=2,f(x2)=1;x3=4,f(x3)=6,则二阶差商f(x1,x2,x3)=()
A.5/2
B.-3
C.11/6
D.2/5
- · 有4位网友选择 D,占比50%
- · 有2位网友选择 B,占比25%
- · 有2位网友选择 C,占比25%
A.5/2
B.-3
C.11/6
D.2/5
求解下列线性规划问题:
(1)max z=x1+2x2,
s.t.2x1+x2≤8,
-x1+x2≤4,
x1-x2≤0,
0≤x1≤3,x2≥0;
(2)min f=-3x1-11x2-9x3+x4+29x5,
s.t.x2+x3+x4-2x5≤4,
x1-x2+x3+2x4+x5≥0,
x1+x2+x3-3x5≤1,
x1无符号限制,xi≥0(j=2,3,4,5);
(3)max x=x1+6x2+4x3,
s.t.-x1+2x2+2x3≤13,
4x1-4x2+x3≤20,
x1+2x2+x3≤17,
x1≥1,x2≥2,x3≥3.
A.c
B.&c
C.%c
D.f
A.c
B.&c
C.%c
D.f
A.1 个.
B.2 个.
C.3 个.
D.4 个.
A.c
B.&c
C.%c
D.f
用单纯形法求解下列线性规划问题:
(1)min f=x1-x2+x3,
s.t.x1+x2-2x3≤2,
2x1+x2+x3≤3,
-x1+x3≤4,
x1,x2,x3≥0;
(2)min f=3-3x2+x3,
s.t.2x1+x2-x3=1,
x2+3x3+x4=7,
xi≥0(i=1,2,3,4);
(3)min f=4-x2+x3,
s.t.x1-2x2+x3=2,
x2-2x3+x4=2,
x2+x3+x5=5,
xi≥0(i=1,2,…,5).
(1)max z=2x1+x2+3x3+x4,
s.t.x1+x2+x3+x4≤5,
2x1-x2+3x3=-4,
x1-x3+x4≥1,
x1,x13≥0,x2x4无符号限制;
(2)min f=3x1+2x2-3x3+4x4,
s.t. x1-2x2+3x3+4x4≤3,
x2+3x3+4x4≥-5,
2x1-3x2-7x3-4x4=2,
x1≥0,x4≤0,x2,x3无符号限制.
用两阶段法求解下列问题:
(1) min f=2x1+x2-x3-x4,
s.t.x1-x2+2x3-x4=2,
2x1+x2-3x3+x4=6,
x1+x2+x3+x4=7,
xj≥0(j=1,2,3,4);
(2)max z=10x1+15x2+12x3,
s.t.5x1+3x2+x3≤9,
-5x1+6x2+15x3≤15,
2x1+x2+x3≥5,
x1,x2,x3≥0;
(3)max z=2x1-x2+2x3,
s.t.x1+x2+x3≥6,
-2x1+x3≥2,
2x2-x3≥0,
x1,x2,x3≥0;
(4)max z=5x1+3x2+6x3,
s.t.x1+2x2+x3≤18,
2x1+x2+3x3≤16,
x1+x2+x3=10,
x1,x2≥0,x3无符号限制.
A.2.1500 -4.7500
B.2.2500 -4.7500
C.2.3500 -4.7500
D.2.4500 -4.7500
为了保护您的账号安全,请在“简答题”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!