Given a function:

$y(x)=\frac{1-x^2}{a{e}^x}$

Plot $y$ with respect to $t$ where $-x$ with an increment $0\mathrm{.}01$ for $a=0,0\mathrm{.}2,0\mathrm{.}5,0\mathrm{.}6,0\mathrm{.}8,1$

Write $x-$axis title