# Reduce or Solve for symbolic equations? Both do not work for mine.

Posted 10 days ago
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 I want to solve the followiwng system of equations: Reduce[{u^e == 1 - u^f, Q == u^e \!$$\*SubsuperscriptBox[\(N$$, $$t$$, $$e$$]\) + u^f \!$$\*SubsuperscriptBox[\(N$$, $$t$$, $$f$$]\), \!$$\*SubsuperscriptBox[\(N$$, $$t$$, $$f$$] == \*FractionBox[$$\*SubscriptBox[\(D$$, $$t$$] - \*SubscriptBox[$$P$$, $$t$$] - Q\ $$(\(-1$$ - t + T)\)\ \*SubsuperscriptBox[$$\[Gamma]\[Sigma]$$, $$\[Epsilon]$$, $$2$$]\), SubsuperscriptBox[$$\[Gamma]\[Sigma]$$, $$\[Epsilon]$$, $$2$$]]\), Subscript[X, t] == \[Theta]^t Subscript[X, 0] + (1 - \[Theta]) Subscript[\[Lambda], t] \!$$\*UnderoverscriptBox[\(\[Sum]$$, $$k = 0$$, $$\(-1$$ + t\)]$$\(\*SuperscriptBox[\(\[Theta]$$, $$k$$]\)[$$- \*SubscriptBox[\(P$$, $$\(-1$$ - k + t\)]\) + \*SubscriptBox[$$P$$, $$\(-k$$ + t\)]]\)\), \!$$\*SubsuperscriptBox[\(N$$, $$t$$, $$e$$] == \*FractionBox[ SubscriptBox[$$X$$, $$t$$], SubsuperscriptBox[$$\[Gamma]\[Sigma]$$, $$\[Epsilon]$$, $$2$$]]\)}, \ Subscript[P, t]] Unfortunately, neither reduce nor solve work here. I get the error message: ". is not a quantified system of equations and inequalities." What does that mean?
 If I write your equations like this eqs = {ue == 1 - uf, Q == ue nte + uf ntf, ntf == (dmq - pt)/g, nte == xt/g} and "forget" the xt - term (which is a complicated function of other (former?) pt's ) Reduce works giving lots of conditions. Reduce[eqs, pt] It is by no means clear what you want to do with your equations, which are really complicatedly written. You should avoid all these sub- and super-scripts