Okay, 1st fact to remember
An A.P. is of the form: , where
Solve equations (1) and (2) simultaneously to obtain your answer.
I need to find first term and common difference for an arithmetic progression where Un denotes the nth term and the sum of the first n terms is denoted Sn.
I am told U5 + U16 = 44 and that S18=3*S10
I cant see a way to find either of them... any help please.