Please someone help me?? or explain/ give hints!!!
1 it is differentiable on the open interval
2 it is continuous on the closed interval
3 f(0)=f(4)=5
SEE...
http://en.wikipedia.org/wiki/Rolle's_theorem
If a real-valued function ƒ is continuous on a closed interval [a,b], differentiable on the open interval (a, b),
and ƒ(a) = ƒ(b), then there is some real number c in the open interval (a, b) such that .
So set 2x-4=0 and solve for x.