Arithmetic series is the sum of an arithmetic sequence. The series is infinite if the number of addends in the series is finite otherwise it is infinite
You can see on the board the meaning of Arithmetic series and its formula
To find the sum of the arithmetic series1. Sn= n(A1+An) 2 if An is given2. Sn+ n/2 [2a+(n-1)d] if An is not given
1. Find the sum of the first 20 terms of the sequence 3, 5, 7....Sn= 20/2 [2(3)+(20-1)2]= 10 [6+ (19) 2]= 10 (6 + 38)= 10 (44)S20= 440
Let no.1 be our example and class let me remind you the assignment of our topic about Arithmetic Series that will be submitted tomorrow
Noted Ma'am
Assignment:Find the sum of the first 16 terms of the sequence 2, 5, 8, . . . .
I should find out what solution to use by finding the variables A1=2, n=16, d=3
I see that the given problem has no An. I should solve this by using the solution Sn=n/2 [2a + (n-1) d]
First thing to do is to write the solution then Substitute and evaluate