Let f be a continuous function in [0,3] and differentiable in (0,3) such that f(3)=0. Then there exist some α∈(0,3) such that
αf1(α)−f(α)=0
2αf1(α)−3f(α)=0
3αf1(α)−f(α)=0
αf1(α)+f(α)=0
Let g(x)=xnf(x)(n>0)g(0)=0,g(3)=0 By using rolls theorem, there exist some α∈(0,3) such that
g1(α)=0⇒αf1(α)+ n f(α)=0,n>0
We can see that for n=1, option(4) is true.