[问题] 方程组求解

[jiaozhiyuan88]

y1 = 276.3 - 0.19 x1 - 0.47 x2 - 10.63 x3 - 12.38 x4 + 2.27 x5 -
6.73 x1*x1 - 5.06 x2*x2 - 12.79 x3*x3 - 1.92 x4*x4 - 10.49 x5*x5 +
0.94 x1*x2 - 1.81 x1*x3 - 11.56 x1*x4 - 6.69 x1*x5 + 2.56 x2*x3 -
0.44 x2*x4 + 1.44 x2*x5 + 0.56 x3*x4 - 0.81 x3*x5 + 1.19 x4*x5
y2 = 146.2 + 0.30 x1 + 1.41 x2 + 7.21 x3 + 6.8 x4 + 1.86 x5 +
1.82 x1*x1 - 2.36 x2*x2 - 2.57 x3*x3 - 0.08 x4*x4 + 1.19 x5*x5 +
1.63 x1*x2 + 1.63 x1*x3 - 0.63 x1*x4 + 0.25 x1*x5 - 0.38 x2*x3 +
1.13 x2*x4 - 1.13 x2*x5 - 0.88 x3*x4 - 1.25 x3*x5 - 1.75 x4*x5
y3 = 84.7 + 2.56 x1 + 3.84 x2 + 9.43 x3 + 12.45 x4 + 0.19 x5 +
1.24 x1*x1 - 1.27 x2*x2 + 1.03 x3*x3 - 0.22 x4*x4 + 1.24 x5*x5 +
1.13 x1*x2 + 2.63 x1*x3 + 2.25 x1*x4 + 0.88 x1*x5 - 3.13 x2*x3 +
3.5 x2*x4 + 0.38 x2*x5 - 5.25 x3*x4 - 1.38 x3*x5 - 0.5 x4*x5
y4 = 75.7 + 0.12 x1 + 0.41 x2 + 0.82 x3 + 1.04 x4 + 0.05 x5 -
0.13 x1*x1 - 0.13 x2*x2 + 0.07 x3*x3 + 0.28 x4*x4 + 0.07 x5*x5 +
0.44 x1*x2 + 0.44 x1*x3 + 0.31 x1*x4 + 0.06 x1*x5 + 0.06 x2*x3 -
0.31 x2*x4 - 0.06 x2*x5 - 0.31 x3*x4 - 0.31 x3*x5 - 0.44 x4*x5
y5 = 0.5227 + 0.0159 x1 + 0.021 x2 - 0.046 x3 + 0.033 x4 -
0.0152 x5 + 0.0018 x1*x1 - 0.0274 x2*x2 - 0.0023 x3*x3 -
0.0107 x4*x4 + 0.0081 x5*x5 + 0.0181 x1*x2 - 0.0019 x1*x3 +
0.0006 x1*x4 - 0.0156 x1*x5 + 0.0294 x2*x3 - 0.0031 x2*x4 +
0.0131 x2*x5 + 0.0044 x3*x4 + 0.0106 x3*x5 - 0.0044 x4*x5
y6 = 0.4736 - 0.0249 x1 - 0.0501 x2 + 0.0612 x3 - 0.0473 x4 +
0.0003 x5 - 0.0302 x1*x1 + 0.02 x2*x2 + 0.0367 x3*x3 +
0.0033 x4*x4 - 0.0302 x5*x5 - 0.0044 x1*x2 - 0.0081 x1*x3 +
0.0081 x1*x4 - 0.0194 x1*x5 - 0.0081 x2*x3 + 0.0131 x2*x4 +
0.0056 x2*x5 + 0.04444 x3*x4 - 0.0031 x3*x5 - 0.0019 x4*x5
y7 = 0.6672 - 0.0011 x1 + 0.0245 x2 - 0.0306 x3 - 0.0363 x4 -
0.0013 x5 + 0.0221 x1*x1 + 0.0284 x2*x2 + 0.0263 x3*x3 +
0.0033 x4*x4 + 0.0159 x5*x5 + 0.0113 x1*x2 - 0.005 x1*x3 +
0.03 x1*x4 + 0.0175 x1*x5 - 0.0325 x2*x3 + 0.0175 x2*x4 -
0.05 x2*x5 + 0.0138 x3*x4 + 0.0038 x3*x5 - 0.0063 x4*x5
y8 = 0.6806 - 0.002 x1 + 0.0045 x2 - 0.0164 x3 + 0.0278 x4 -
0.002 x5 + 0.0039 x1*x1 - 0.0108 x2*x2 + 0.0039 x3*x3 -
0.0066 x4*x4 - 0.0066 x5*x5 - 0.0081 x1*x2 + 0.0006 x1*x3 -
0.0031 x1*x4 + 0.0031 x1*x5 - 0.0069 x2*x3 - 0.0031 x2*x4 +
0.0031 x2*x5 + 0.0094 x3*x4 + 0.0044 x3*x5 + 0.0031 x4*x5
210 < y1 < 240
130 < y2 < 150
100 < y3 < 120
76 < y4 < 78
0.6 < y5 < 1.0
0 < y6 < 0.3
0.7 < y7 < 1.0
0.7 < y8 < 1.0
-1.547 < xj < 1.547, j = 1, 2, 3, 4, 5
求解符合条件的
{x1，x2，x3，x4，x5}及每组解对应的{y1,y2,y3,y4,y5,y6,y7,y8}
非常希望有高手指导，最好能有详细说明！
先谢了.....