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[求助]谁能帮忙看一下这个方程如何解?

pig3 发布于 2007-03-27 10:32, 701 次点击
0.95*z-0.32*x-5.427=-0.27*sqrt[(0.95x+0.32z)^2+y^2]
x+y*1.2=120.59+128.96
x/a+y/b+z/c=1

其中a、b、c是常数,求解x、y、z三个未知量的值,不知道用matlab能不能直接求解,要如何做?
3 回复
#2
insist11042007-03-27 14:06

去help中找一下fsolve!

#3
abingchem2007-03-27 17:39
如果你不给a,b,c设定值,那么只能用符号解法,但即使用maple解出来的结果也不是人能分析的
这是maple的结果:
{y = -.8333333333*RootOf((50462100*a^2*b^2-2348363520*c*a*b^2+1956969600*a^2*b*c-3222126144*c^2*b^2+5370210240*c^2*b*a-2237587600*c^2*a^2)*_Z^2+1340135965392*c^2*b-3222126144*c^2*b^2+37120680000*b^2*c+11243627271225*b^2-139346220901489*c^2-7719554745000*b*c+(-103464783000*b^2*a-1340135965392*c^2*b+2348363520*c*a*b^2-37120680000*b^2*c+1116779971160*c^2*a-5370210240*c^2*b*a+6444252288*c^2*b^2-457427863680*a*b*c)*_Z, label = _L1)*a+207.9583333, z = 0.4166666667e-1*c*(-24.*RootOf((50462100*a^2*b^2-2348363520*c*a*b^2+1956969600*a^2*b*c-3222126144*c^2*b^2+5370210240*c^2*b*a-2237587600*c^2*a^2)*_Z^2+1340135965392*c^2*b-3222126144*c^2*b^2+37120680000*b^2*c+11243627271225*b^2-139346220901489*c^2-7719554745000*b*c+(-103464783000*b^2*a-1340135965392*c^2*b+2348363520*c*a*b^2-37120680000*b^2*c+1116779971160*c^2*a-5370210240*c^2*b*a+6444252288*c^2*b^2-457427863680*a*b*c)*_Z, label = _L1)*b+20.*RootOf((50462100*a^2*b^2-2348363520*c*a*b^2+1956969600*a^2*b*c-3222126144*c^2*b^2+5370210240*c^2*b*a-2237587600*c^2*a^2)*_Z^2+1340135965392*c^2*b-3222126144*c^2*b^2+37120680000*b^2*c+11243627271225*b^2-139346220901489*c^2-7719554745000*b*c+(-103464783000*b^2*a-1340135965392*c^2*b+2348363520*c*a*b^2-37120680000*b^2*c+1116779971160*c^2*a-5370210240*c^2*b*a+6444252288*c^2*b^2-457427863680*a*b*c)*_Z, label = _L1)*a-4991.+24.*b)/b, x = RootOf((50462100*a^2*b^2-2348363520*c*a*b^2+1956969600*a^2*b*c-3222126144*c^2*b^2+5370210240*c^2*b*a-2237587600*c^2*a^2)*_Z^2+1340135965392*c^2*b-3222126144*c^2*b^2+37120680000*b^2*c+11243627271225*b^2-139346220901489*c^2-7719554745000*b*c+(-103464783000*b^2*a-1340135965392*c^2*b+2348363520*c*a*b^2-37120680000*b^2*c+1116779971160*c^2*a-5370210240*c^2*b*a+6444252288*c^2*b^2-457427863680*a*b*c)*_Z, label = _L1)*a}
#4
pig32007-03-27 22:43
thanks,我回去看一下
1