Question

三元一次方程求解 matlab 这个求解错在哪里？

>> syms a b c f g d e h;
>> syms X Z Y;
>> [X,Z,Y]=solve('a/(f+g)+a*(d+e+f+g)/(f+g)/X=(Z-a*(d+e+f+g)/(f+g))/h+(Z-a*(d+e+f+g)/(f+g))/Y','b/(f+g)+b*(d+f+g)/(f+g)/X=(Z-b*(d+f+g)/(f+g))/h+(Z-b*(d+f+g)/(f+g))/Y','c/(f+g)+c*(d+f)/(f+g)/X=(Z-c*(d+f)/(f+g))/h+(Z-c*(d+f)/(f+g))/Y','X,Z,Y');

警告: Support of character vectors that are not valid variable names or define a number will be removed in a future
release. To create symbolic expressions, first create symbolic variables and then use operations on them.
> In sym>convertExpression (line 1559)
In sym>convertChar (line 1464)
In sym>tomupad (line 1216)
In sym (line 179)
In solve>getEqns (line 405)
In solve (line 225)
警告: Support of character vectors that are not valid variable names or define a number will be removed in a future
release. To create symbolic expressions, first create symbolic variables and then use operations on them.
> In sym>convertExpression (line 1559)
In sym>convertChar (line 1464)
In sym>tomupad (line 1216)
In sym (line 179)
In solve>getEqns (line 405)
In solve (line 225)
警告: Support of character vectors that are not valid variable names or define a number will be removed in a future
release. To create symbolic expressions, first create symbolic variables and then use operations on them.
> In sym>convertExpression (line 1559)
In sym>convertChar (line 1464)
In sym>tomupad (line 1216)
In sym (line 179)
In solve>getEqns (line 405)
In solve (line 225)
警告: Support of character vectors that are not valid variable names or define a number will be removed in a future
release. To create symbolic expressions, first create symbolic variables and then use operations on them.
> In sym>convertExpression (line 1559)
In sym>convertChar (line 1464)
In sym>tomupad (line 1216)
In sym (line 179)
In solve>getEqns (line 405)
In solve (line 225)
警告: Do not specify equations and variables as character vectors. Instead, create symbolic variables with syms.
> In solve>getEqns (line 445)
In solve (line 225)
>>

Answer 1

用matlab求解三元一次方程求解出现上述错误警告，其主要的原因是符号变量太多了。建议给出a、 b、 c、 f、 g、 d、 e、 h的具体数值，然后再求解。