Let $c_0,c_1,c_2,\ldots ,c_n$ be constants such that :
$$c_0+\frac{c_1}{2}+\ldots+\frac{c_{n-1}}{n}+\frac{c_n}{n+1}=0$$
I have to prove that the equation: $$c_0+c_1x+\ldots+c_nx^n=0$$
Has a real solution between 0 and 1.
Didn't know how to start...I thought that maybe I could use something about derivative...But I'm lost... Any help,much appreciated!!!