I am trying to break a long equation over multiple lines. It is here as follows:

&\quad\cdot q_{2}^{i(t)sA(t+1)+(iA(t)+iC(t))sB(t+1)+(iA(t)+iB(t))sC(t+1)}\\

But when I try and pdflatex the file, I get !Missing } inserted. And it doesn't run. I don't know why it's trying to put in extra brackets when they are not needed. And the file runs without the split environment (but I need to put it in since otherwise the equation flows off the page)

Any help??

  • Remove first { in {q_{1}^{, first line and the last } in -sC(t+1)}} last line. – user11232 Mar 29 '13 at 13:15
  • Welcome to TeX.SX. A tip: If you indent lines by 4 spaces, then they're marked as a code sample. You can also highlight the code and click the "code" button ({}) or hit Ctrl+K. – Claudio Fiandrino Mar 29 '13 at 13:29
  • You can make this much easier by replacing all the exponents with some simple notations and explain them separately. – g.kov Mar 29 '13 at 14:27
  • 2
    It's a common misconception to think that one has to write \prod_{i=1}^{n}{a_{i}}; while the braces for the limits are necessary, those around a_{i} aren't and actually shouldn't be used. – egreg Mar 29 '13 at 14:41
  • Also, just so you know, it's best to use \mathbf{q} to get a bold upright q in math. For instance, if this equation was inside a theorem whose text was set in italic, the \textbf{q} would render as a bold italic q; but a \mathbf{q} would still render as a bold upright q. – MSC Mar 29 '13 at 16:12

Here is a working version of your code. You don't need to wrap the product itself into {}. For real grouping I used curly braces.


        &= \prod\limits_{t=0}^{36} \Bigl\{ q_{1}^{iB(t)sB(t+1)+iC(t)sC(t+1)} \\
        &\quad \cdot q_{2}^{i(t)sA(t+1)+(iA(t)+iC(t))sB(t+1)+(iA(t)+iB(t))sC(t+1)} \\
        &\quad \cdot (1-q_{2}^{i(t)})^{sA(t)-sA(t+1)} \\
        &\quad \cdot (1-q_{1}^{iB(t)}q_{2}^{iA(t)+iC(t)})^{sB(t)-sB(t+1)} \\
        &\quad \cdot (1-q_{1}^{iC(t)}q_{2}^{iA(t)+iB(t)})^{sC(t)-sC(t+1)} \Bigr\}



| improve this answer | |
  • 1
    I would align the subsequent factors under the first factor, not the \prod. – mafp May 22 '13 at 10:26
  • I like your suggestion, but according to the question, this is what OP wanted. – Henri Menke May 22 '13 at 16:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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