# test

• Oct 24th 2010, 11:25 PM
questionboy
test
$y''+2y'+5y=\left\{\begin{array}{cc}0,&\mbox{ if }
t\leq t\leq\frac{\pi}{2}\\1, & \mbox{ if } t>\frac{\pi}{2}\end{array}\right$

where $y(0)=0, y'(0)=0$
• Oct 25th 2010, 02:37 AM
Opalg
Alternatively, you can use the cases environment, which is designed for this purpose. Notice that it aligns items to the left (which is how printers set such expressions) instead of centering them.

$y''+2y'+5y=\begin{cases}0&\text{if }
t\leq t\leq\frac{\pi}{2},\\1 & \text{if } t>\frac{\pi}{2},\end{cases}$