Find the sum to n term of the A.P. 5, 2, −1, −4, −7, ...,
Answers
Answered by
6
Answer:
The sum to n term of the A.P. is n/2 [13 – 3n]
Step-by-step explanation:
Given :
A.P. 5, 2, −1, −4, −7, ...,
Here, first term, a = 5 , common difference, d = 2 - 5 = -3
By using the formula ,Sum of nth terms , Sn = n/2 [2a + (n – 1) d]
Sn = n/2 [10 + (n – 1) -3]
Sn = n/2 [10 - 3n + 3]
Sn = n/2 [13 – 3n]
Hence, the sum to n term of the A.P. is n/2 [13 – 3n]
HOPE THIS ANSWER WILL HELP YOU...
Answered by
6
SOLUTION
We have the A.P. 5, 2,-1,-4,-7.....
Where,
a= 5
Common difference= 2-5= -3
So,Formula
=)nth term= an = n/2[ 2a+(n-1)d]
=) an= n/2 [2×5 +(n-1)-3]
=) an= n/2[ 10-3n +3]
=) an= n/2 [13-3n]
Hence,
AP is n/2 [13-3n]
hope it helps ✔️
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