I have a function ${e^{ - \frac{{a{x^2} + b{x^2}}}{2}}}\left[ {C - \frac{{{x^2}d}}{2}} \right]$,
Where, $C > \frac{{{x^2}d}}{2}$ and $C,a,b,d > 0$. I was trying to find the upper bound of the function in the form of ${x^2} \times \left\{ {f\left( {.....} \right)} \right\}$.
I tried but could not extract $x^2$ outside the bracket for upper bound. I dont know if it is impossible or I am missing some inequality relation. Thank you.