2y''+(y')^3=0
y(0)=5
y'(0)=0
i need to deside on :
A.is it increasing or decreasing or a constant on the surroundings of 0
B.does it has a solution
C.does it have two solutions in which one of the increasing the other is decreasing

and i can solve it:
z=y'
i got 2/z=y+c
2/y'=y+c

but when i want to find C
i get
2/0=5+c
??

z=dy/dx=y'
dz/dy=zz'
2z'z+z^3=0