Recent content by ings

  1. I

    Solve Series P: Sum of First n Terms & Arithmetic Progression

    i am not sure whether it's correct... i do it in this way: let S2n= f(2n) then Sn=f(n) f(2n)= 20n-4n2 = 10(2n)- (2n)2 hence, f(n)= 10n - n2...
  2. I

    Solve Series P: Sum of First n Terms & Arithmetic Progression

    But the question only mentions that sentences ...
  3. I

    Solve Series P: Sum of First n Terms & Arithmetic Progression

    CAN U ALL HELP ME TO SOLVE THIS QUESTION? I don't know how to start... The sum of the first 2n terms of a series P is 20n-4n2. Find in terms of n, the sum of the first n terms of this series. Show that the series is an arithmetic series.