I am getting an error in the following code on my LaTeX template. But the same code is running on MathJax.
\begin{align*}
1. {\log_{a}a} = 1\ \mbox{log of a number to the same base is 1}
\end{align*}
Please help.
[Tex/LaTex] \begin{align*} … \end{align*} is not working
align
Related Solutions
TeX is great for math typesetting; so it's unlikely that a formula like that is so complicated to input:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\section{Situation 1}
\begin{equation*}
J_{(j)} =
\sum_{i:r(i,j)=1} \bigl((\theta^{(j)})^{T} x^{(i)} - Y_{i,j}\bigr)^2 +
\frac{\lambda}{2}\sum_{k=1}^{n}\bigl(\theta_{k}^{(j)}\bigr)^2
\end{equation*}
\end{document}
There should never be \textsuperscript inside a formula.
Using \bigl and \bigr in the first formula makes the parentheses slightly bigger, which is good for reading in this case. Since they are almost necessary in the furst summation, I used them also in the second one, for symmetry.
The align environment is for multiline displays; if you want the equation numbered, then use equation instead of equation*.
But in any case, the contents of equation, align and similar environments is already assumed to be math, so adding $ will give errors.
None of the align, gather and equation environments must be typeset within of a $...$ pair, since those environments start the math mode for themselves. This is true for the starred variants of the mentioned environments as well.
Some side remarks:
- Use
\sininstead ofsin-- it's a math operator which should not be typeset in italics. \dfrac{}{}is (sometimes) a better replacement for nicer fractions.\DeclairedPairedDelimiters{\abs}{\lvert}{\rvert}is much better than|some stuff|
\documentclass{article}
\usepackage{mathtools}
\DeclarePairedDelimiter{\abs}{\lvert}{\rvert}
\begin{document}
%$
%m\dfrac{v^2}{r}=qvB\\
%\dfrac{2qV}{r}=qvB\\
%\dfrac{2qV}{r}=qB\sqrt{\dfrac{2qV}{m}}\\
%\dfrac{V}{r}=B\sqrt{\dfrac{q}{2m}}\sqrt{V}\\
%$
\begin{align*}
\abs{\vec{F}} &=\abs{q}\abs{\vec{v}}\abs{\vec{B}}\abs{\sin(\theta)}\\
m\dfrac{v^2}{r}& =qvB\\
\dfrac{2qV}{r} &=qvB\\
\dfrac{2qV}{r} & =qB\sqrt{\dfrac{2qV}{m}}\\
\dfrac{V}{r} &=B\sqrt{\dfrac{q}{2m}}\sqrt{V}\\
\end{align*}
\begin{align*}
\dfrac{V}{r} &=\lambda\sqrt{V} &\lambda\equiv B\sqrt{\dfrac{q}{2m}}
\end{align*}
\begin{gather*}
\dfrac{V}{r}=\lambda\sqrt{V},\lambda\equiv B\sqrt{\dfrac{q}{2m}}
\end{gather*}
\begin{equation}
\dfrac{V}{r}=\lambda\sqrt{V},\lambda\equiv B\sqrt{\dfrac{q}{2m}}
\end{equation}
\end{document}
Best Answer
The error is due to the blank line, but also do not use
alignoralign*for 1-line equations with no alignment, the vertical spacing will be wrong. If the 1. is not mathematics but part of an enumerated list then perhaps