# Question:fsolve refuses to work

## Question:fsolve refuses to work

Maple

Hi, i have the following equation system, for which i  already know the solution.

restart:

s1:=(r1*r2-1/(400000000*c1*c2))*(r1+r2)/((r1+r2)^2+(-1/(20000*c1)-1/(20000*c2))^2)
+(-1/20000/c1*r2-1/20000*r1/c2)*(-1/(20000*c1)-1/(20000*c2))/((r1+r2)^2+
(-1/(20000*c1)-1/(20000*c2))^2) = 611.0987791:

s2:=(-1/40000/c1*r2-1/40000*r1/c2)*(r1+r2)/((r1+r2)^2+(-1/(40000*c1)
-1/(40000*c2))^2)-(r1*r2-1/(1600000000*c1*c2))*(-1/(40000*c1)-
1/(40000*c2))/((r1+r2)^2+(-1/(40000*c1)-1/(40000*c2))^2) = -8334.070796:

s3:=(r1*r2-1/(1600000000*c1*c2))*(r1+r2)/((r1+r2)^2+(-1/(40000*c1)-1/(40000*c2))^2)
+(-1/40000/c1*r2-1/40000*r1/c2)*(-1/(40000*c1)-1/(40000*c2))/((r1+r2)^2
+(-1/(40000*c1)-1/(40000*c2))^2) = 611.0619469:

s4:=(-1/20000/c1*r2-1/20000*r1/c2)*(r1+r2)/((r1+r2)^2+(-1/(20000*c1)-
1/(20000*c2))^2)-(r1*r2-1/(400000000*c1*c2))*(-1/(20000*c1)
-1/(20000*c2))/((r1+r2)^2+(-1/(20000*c1)-1/(20000*c2))^2) = -16667.03663:

vars:={r1=1500,r2=1000,c2=2e-9,c1=1e-9};

fsolve({s1,s2,s3,s4},vars);

Maple returns it unevaluated, altough i give a perfect starting point for numerical evaluation. The solution is correct, i tested it:

seq(eval(s||i,vars),i=1..4);

611.0987790 = 611.0987791, -8334.070796 = -8334.070796, 611.0619471 = 611.0619469, -16667.03663 = -16667.03663

what's wrong ?

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