I have a document I am trying to copy to learn TeX. Here is what I have encountered:alt text How can I have the "or" in the equation. This is what I have right now:

\[ f = ma; \] 
But $a$ is the change in velocity,

\[ f = m \frac{dv}{dt};\]
\[ f = m  \frac{d^2y}{dt^2};\]

Edit: Trying out Stefan's answer alt text


Use the amsmath package and the commands \text{...} for text in the formula or \intertext{...} for text between the lines of multi-line formulas. For example:

  f &= ma;\\ \intertext{But $a$ is the change in velocity} 
  f &= m \frac{dv}{dt};\\ \intertext{or} 
  f &= m  \frac{d^2y}{dt^2};

One advantage of align* to \[ ... \] is that you can align the equations on relation symbols.

If you wish to put or in the same line, you could use \text and flalign* :

  && f &= ma;&\\ \text{or} && f &= m \frac{dv}{dt};&\\ \text{or}  &&f &= m  \frac{d^2y}{dt^2};

flalign example

  • 7
    & is used both for specifying the alignment position and as column separator, alternating. In columns of formulas, &= means that at = would be aligned, a following & would end the column, like in a table. && has been used to skip a column, i.e. to create an empty column.
    – Stefan Kottwitz
    Aug 13 '10 at 16:53

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.