The sum of nth term of an AP is 5n-n^2,find the nth term
Answers
Answered by
2
Answer:
6 - 2n
Step-by-step explanation:
Sn=5n-n^2
S1=5 (1) - (1)^2
=5 - 1
=4=a1
S2=5 (2) - (2)^2
=10 - 4
=6
a2=S1 - S2
=6 - 4
=2
d=a2 - a1
=2 - 4
= - 2
an= 2a + (n - 1)d
=2 (4)+ (n - 1)(- 2)
=8 - 2 n + 2
= 6 - 2n
Similar questions