Meir Achuz Science Advisor Homework Helper Gold Member Messages 3,742 Reaction score 249 Nov 27, 2006 #32 aligator123 said: at the last equation this equation remains Pn'(1)=t*(n+2)(n+1)/2 The t can't be there. You have to change n in the original sum to n-1.
aligator123 said: at the last equation this equation remains Pn'(1)=t*(n+2)(n+1)/2 The t can't be there. You have to change n in the original sum to n-1.