《高等应用数学问题的MATLAB求解》——第6章习题代码

（1）

>> syms x y z;
>> f1(x,y,z)=24*x*y-x^2-y^2-x^2*y^2-13;
>> f2(x,y,z)=24*x*z-x^2-z^2-x^2*z^2-13;
>> f3(x,y,z)=24*y*z-y^2-z^2-y^2*z^2-13;
>> [x0,y0,z0]=vpasolve(f1,f2,f3);
>> norm(f1(x0,y0,z0)),norm(f2(x0,y0,z0)),norm(f3(x0,y0,z0))

>> syms x y z;
>> f1(x,y,z)=x^2*y^2-z*x*y-4*x^2*y*z^2-x*z^2;
>> f2(x,y,z)=x*y^3-2*y*z^2-3*x^3*z^2-4*x*z*y^2;
>> f3(x,y,z)=y^2*x-7*x*y^2+3*x*z^2-x^4*z*y;
>> [x0,y0,z0]=vpasolve(f1,f2,f3);
>> norm(f1(x0,y0,z0)),norm(f2(x0,y0,z0)),norm(f3(x0,y0,z0))