Asked by nakiera
find the sum of the 1st 70 terms of the arithmetic sequence 16,6,-4,-14
Answers
Answered by
MathMate
The nth term of the sequence is:
T(n)=26-10n, so
T(1)=26-10*1=16,
T(2)=26-10*2=6,
....
T(70)=26-10*70=-674
The sum of an arithmetic sequence is the average of the first and last terms multiplied by the number of terms.
Here, we have
Sum = (T(1)+T(70)*70/2
I'll let you take it from here.
T(n)=26-10n, so
T(1)=26-10*1=16,
T(2)=26-10*2=6,
....
T(70)=26-10*70=-674
The sum of an arithmetic sequence is the average of the first and last terms multiplied by the number of terms.
Here, we have
Sum = (T(1)+T(70)*70/2
I'll let you take it from here.