For 5 + 16 + 27 + 38 + ..., find the sum of the first n terms, as a function of n.
+23246 Each of the terms of the series 5 + 16 + 27 + 38 + ...
can be determined by this formula: 11n - 6 where n is the number of the term.
The formula for the sum of an arithmetic series is: Sum = n·(first + last) / 2
n is the number of terms
the first term is 5
the last term is 11n - 6
so: Sum = n·[ 5 + (11n - 6) ] / 2
= n·[ 5 + 11n - 6 ] / 2
= n·[ 11n - 1 ] / 2
+23246 Each of the terms of the series 5 + 16 + 27 + 38 + ...
can be determined by this formula: 11n - 6 where n is the number of the term.
The formula for the sum of an arithmetic series is: Sum = n·(first + last) / 2
n is the number of terms
the first term is 5
the last term is 11n - 6
so: Sum = n·[ 5 + (11n - 6) ] / 2
= n·[ 5 + 11n - 6 ] / 2
= n·[ 11n - 1 ] / 2
