4

Wikipedia has a great looking equation of rational bezier curves at https://en.wikipedia.org/wiki/B%C3%A9zier_curve#Rational_B.C3.A9zier_curves.

It's multi line in that there is an equation above the division and an equation below the division, and it looks nice (easy to read).

I'm trying to do that as well, but for some reason, my formula always shows up as single line.

Here is my attempt:

$\sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iW_iP_i / \sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iW_i&bg=000000&fg=ffffff$

Anyone have any idea how to make it multiline, like wikipedia does?

Alan Wolfe
  • 155

2 Answers2

5

You should use the equation enviroment of the amsmath package and the \frac{}{} command like this:

\usepackage{amsmath}
\begin{equation*}
\text{\bf{B}}(t) = \frac
                % Nominator
                {\sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iw_i\text{\bf{P}}_i}
                % Denominator
                {\sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iw_i}
\end{equation*}

So you will be getting an equation like this:

enter image description here

Andrew Swann
  • 95,762
Alder Miguel
  • 392
  • 1
  • 11
3
\[
\frac{\sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iW_iP_i}
     {\sum\limits_{i=0}^n\binom {n} {i}(1-t)^{n-i}t^iW_i}
\]

For multiline equations use package amsmath and one of the align environments.