求解方程组,用已知量表示未知量,手算或MATLAB算均可,给个正确答案就成.U1/U2=R1*(30.11+R2)/R2/(30.11+R1)U11/U22=R11*(30.11+R2)/R2/(30.11+R11)R11=R1*R/(R1+R)其中,U1,U2,U11,U22,R为已知量,R11为中间

Question

求解方程组,用已知量表示未知量,手算或MATLAB算均可,给个正确答案就成.
U1 / U2=R1 * (30.11+R2) / R2 / (30.11+R1)
U11 / U22=R11 * (30.11+R2) / R2 / (30.11+R11)
R11 = R1 * R / (R1+R)
其中,U1,U2,U11,U22,R为已知量,R11为中间量,R1,R2为未知量,现在要用已知量表示未知量.

Answer 1

matlab程序如下：
>> syms u1 u2 u11 u22 r r11 r1 r2;
y1=sym('u1/u2=r1*(30.11+r2)/r2/(30.11+r1)');
y2=sym('u11/u22=r11*(30.11+r2)/r2/30.11+r11');
y3=sym('r11=r1*r/(r1+r)');
>> [r11,r1,r2]=solve(y1,y2,y3,r11,r1,r2)
结果如下：
r11 =

-.10000000000000000000000000000000e-1*r*(.25000000000000000000000000000000e35*u22*u1-.25000000000000000000000000000000e35*u11*u2)/(8302889405513118565260710727333.*u22*u1*r-.25000000000000000000000000000000e33*u11*u2+.25000000000000000000000000000000e33*u2*r*u22)



r1 =

-1.*(.25000000000000000000000000000000e35*u22*u1-.25000000000000000000000000000000e35*u11*u2)*r/(-.25000000000000000000000000000000e35*u1+.83028894055131185652607107273330e33*u1*r+.25000000000000000000000000000000e35*r*u2)/u22



r2 =

-30.110000000000000000000000000000*r*(.25000000000000000000000000000000e35*u22*u1-.25000000000000000000000000000000e35*u11*u2)/(-.75275000000000000000000000000000e36*u1*u11+.77775000000000000000000000000000e36*u22*u1*r+.25000000000000000000000000000000e35*u11*r*u1-.25000000000000000000000000000000e35*u11*r*u2)
r11是中间变量不用管,在r1和r2中类似“.123”表示‘“0.123”,e后面数字是科学计数法的幂次项.