1

i want to write like this 

        /ki    if 0<I<IO
       | 
t(i)= <
       |
        \c     if I>Io

here is curly bracket

Mico
  • 506,678
Muhammad Usman
  • 11
  • 5
    Welcome to TeX SX! You should use the cases environment. See the documentation of amsmath, § 3.7, Alignment building blocks. See also mathtools, § 3.4.3, More cases-like environments. – Bernard Jul 21 '19 at 11:57
  • Irrespective of the left brace, I don't understand very well what the formula is supposed to be. – Bernard Jul 21 '19 at 12:22

1 Answers1

1

As has already been suggested in the comments, it looks like a cases environment is what you need.

enter image description here

\documentclass{article}
\usepackage{amsmath} % for 'cases' environment
\begin{document}
\[
t(i) = 
\begin{cases}
k_i & \text{if $0<i<i_0$}\\
c   & \text{if $i>i_0$} 
\end{cases}
\]
\end{document}
Mico
  • 506,678