# Can anybody post result of provided input to Mathematica?

Posted 10 years ago
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 Hello to everybody! Can anybody post result of this input to Mathematica?Reduce[1/4 (-1 + 4 c E^(-(1/2) t1 v1) + E^(t2 v1)) \[Alpha] - ((-1 +        E^(t2 v1)) \[Psi]11)/(2 v1) >= \[Alpha] && \[Alpha] > 0 &&   v1 > 1 && t1 > 0 && t2 > 0, c, Reals]What i seeSolve::nsmet: This system cannot be solved with the methods available to Solve. >>Is it a bug or i just don't understand something?
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Posted 10 years ago
 Thanks for pointing out the typo, I just corrected it. It seems that Mathematica knows how to handle the equation but the inequality: Probably this is a part that needs improvements.
Posted 10 years ago
 So, it is a bug, right? (And it does not depend on whether i use Subscript[]s)P.S. And thanks for advice to use CoefficientList! But also i should note that your usage seems to be erroneous since coefficients start with power 0. So the coefficient at c is always positive. So, it seems to be a bug.
Posted 10 years ago
 Also, please note that you may have to sepcify the behavior of the coefficient below to solve for the inequalityYou may want to replace it with a symbol first and then specify its domain before you reduce the given inequality because the sign of the coefficient of c matters.
Posted 10 years ago
 I think this expression should work in Mathematica. If I use the simpler notation in the expression, I can rewrite it asexpr = 1/4 (-1 + 4  c  E^(-(1/2) t1 v1) + E^(t2 * v1)) \[Alpha] - ((-1 + E^(t2 *v1)) \[Psi]11)/(2 v1)This is indeed a simple polynomial in terms of c:In[93]:= PolynomialQ[expr, c]Out[93]= TrueThe coefficients areTherefore you can either find the solution via:Solve[expr==\[alpha],c] Or use the coefficients in the list above (the first over the second).
Posted 10 years ago
 Also if you would use code without Subscript but using a simpler notation like t1 or v1, the code would look much more readable here on Community posts.
Posted 10 years ago
 Hi there, Solve has to be used for polynomial equations, Reduce for transcendental ones. Nevertheless, neither Reduce nor FindInstance succeeded with this. Possibly you should state also something about Subsuperscript[\[Psi], 1, 1]shouldn´t you?
Posted 10 years ago