Mathematica Stack Exchange is a question and answer site for users of Mathematica. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I can't seem to solve the general quadratic equation:

 Solve[ax^2 + bx + c == 0, x]

 Out[299]= {}

It just outputs the empty list. How do I solve this equation?

share|improve this question

closed as off-topic by m_goldberg, Artes, R. M. Oct 21 '13 at 3:55

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question arises due to a simple mistake such as a trivial syntax error, incorrect capitalization, spelling mistake, or other typographical error and is unlikely to help any future visitors, or else it is easily found in the documentation." – m_goldberg, Artes, R. M.
If this question can be reworded to fit the rules in the help center, please edit the question.

up vote 4 down vote accepted

Firstly,you must know bx is different from b x,because bx is only a varible while b x are two varibles.

Solve[a x^2 + b x + c == 0, x]

{{x -> (-b - Sqrt[b^2 - 4 a c])/( 2 a)}, {x -> (-b + Sqrt[b^2 - 4 a c])/(2 a)}}

Attention the blank space between a and x^2.Good luck!

share|improve this answer
@Tyler Durden,when a constant times a varible,you could not left a blank space between them or use * to replace Times. – Shutao Tang Oct 20 '13 at 9:22

Not the answer you're looking for? Browse other questions tagged or ask your own question.