MATH HELP
posted by AKUMA .
Law of Gravitationfind an expression for the magnitude of the initial velocity that a projectile must possess in order to leave the earth when air friction is negelcted.
The gravitational constant is given as G= 6.67428*10^11 m^3 kg^1 s^2
Please give lots of details in answer

I will be happy to critique your work.
You need to relate initial KE to total gravitational PE from the surface of Earth to infinity. 
Can you please give me a website that would help answer this question