I I'm trying to solve this problem with mathematica but the code keeps giving me an error.
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1 Answer
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Eq1 = x1'[t] == x1[t] + x2[t] + x3[t] + Exp[t];
Eq2 = x2'[t] == -x1[t]^2 + x2[t]^2 + x3[t]^2 + Cos[10*t];
Eq3 = x3'[t] == x1[t] - x2[t] + x3[t] + Sin[5*t];
sol = First@NDSolve[{Eq1, Eq2, Eq3, x1[0] == 1, x2[0] == -1, x3[0] == 1},
{x1[t], x2[t], x3[t]}, {t, 0, 5}]
Plot[(x1[t]^2 + x2[t]^2 + x3[t]^2)^(1/2) /. sol, {t, 0, 5}]
DSolveto get an idea how to do that. If have that code and it does not work, people would need to see it (i.e. you should post it) otherwise it's not possible to identify the issue. $\endgroup$