Several "equations" in the same line

Question

\begin {eqnarray}
P(N(t)=n)=P(T_{n}\leq t)- P(T_{n+1}\leq t)=e^{-\lambda*t}*\frac {(\lamda*t)^{n}}{n!}
\end {eqnarray}

I want to write this in latex however and it gives me an error, can I help me?

Answer 1

Error cleared (\lamda replaced with \lambda):

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin {equation}
P(N(t)=n)=P(T_{n}\leq t)- P(T_{n+1}\leq t)=e^{-\lambda*t}*\frac {(\lambda*t)^{n}}{n!}
\end {equation}

\end{document}