# How to use Reduce to find com

Posted 9 years ago
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 I tried to solve the following set of equations $$- v_+ = C_1 \sinh (C_2) \\ -v_+ = \sinh(-s_+ q + C_2),$$ where $v_+$, $s_+$ and $q$ are constants and I try to solve for $C_1$ and $C_2$ using this code line - Solve[-vplus == C*sinh[B] && -vplus == C*sinh[-S*q + B], {C, B}] But I get this message - Inverse functions are being used by Solve, so some solutions may not \ be found; use Reduce for complete solution informationHow can I use Reduce here to get complete solution?
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Posted 9 years ago
 You wrote the equations in Latex in one form, then in the Mathematica code you used different symbols. little confusing. Let me write your equations, and instead of using -v, just use v since it is the same. And used lowerCaseLetters. Since C is actually a Mathematica symbol. Not a good idea to use UpperCase first letter in Mathematica. So your equations are basically these  eq = {v == c1*Sinh[c2], v == Sinh[-s q + c2]} To use Reduce  Reduce[eq, {c1, c2}, Reals] And to obtain a solution with no warnings  Solve[eq, {c1, c2}, Reals] 
Posted 9 years ago
 Thank you very much for the corrections Nasser! It does though give me a message that this equations cannot be solved with the methods available to Solve. But I don't understand from the explanations which of the other functions can solve this type of system of equations.. Attachments:
Posted 9 years ago
 I forgot one line. I had to convert to exponential form first and forgot to paste the line.. If you can try this. No warnings. V 10.02. ClearAll[c1, c2, s, q]; eq = { v + c1*Sinh[c2] == 0 , v + Sinh[-s*q + c2] == 0}; eq = TrigToExp[eq]; Reduce[eq, {c1, c2}, Reals] Solve[eq, {c1, c2}, Reals] 