@vv

A 3d visualization is what I hoped for. If it's not possible then I gotta find another way to tackle the problem. Thanks anyway for the info.  

@acer 

I have, but the result is not as smooth as I expected. I was wondering if there's another way.

@Mariusz Iwaniuk 

Sorry for the inconvenience. I'm pretty new to the community. I added the inequality by the Maple Math button up here. I thought it does it. Here it is in it's readable format:

0 <= -2*sqrt(4+2*a^2*(1-sqrt(1+8*alpha*m/a^3))/alpha)*(1+2*alpha*(2-a^2*(1-sqrt(1+8*alpha*m/a^3))/(2*alpha))/(3*a^2))/a