Math & Science ⇒ displaying cases based formula

[huu2014]

Hello,
Good day,
I am writing a cases based formula. However, only the bracket symbol is display, not the whole formula. is there specific latex package for greek letters?

using:
ubuntu 14.04
Latex 2016
RStudio 1.01.

# Latex packages
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{latexsym}

Code: Select all

\[
\begin{cases}
   F(y) =
          \frac{x^{(\lambda)} - 1}{(\lambda)}      $\text{if \lambda \neq 0$;} \\
          \log(x)                                   $\text{if \lambda  \eq 0$}

\end{cases}
\]

Please, can any one give me hint?.

thank you in advance

[Johannes_B]

I'm not sure, but i thik you want the following?

Code: Select all

\documentclass{article}
\usepackage{mathtools}
\begin{document}
\[
		F(y) =
	\begin{cases}
		\frac{x^{(\lambda)} - 1}{(\lambda)}       &\text{if } \lambda \neq 0; \\
		\log(x)                                   &\text{if } \lambda  =  0
	\end{cases}
\]
\end{document}

[huu2014]

Johannes_B,
Thanks a lot. it worked.