2.) The sum of 1st 'n' terms of an
AP is given by (n2+8n). Find the 12th
term of AP. Also find the nth term of the AP
Answers
Answered by
4
sum of first n terms = n²+8n
Sn = n/2[ a+an] = n² +8n
n/2[a+ an] = n(n+8)
a+an = 2×(n+8)
a+an = 2n+16
an = 2n+16 -a .......(1) is nth term
we have to find a12
n= 12
put in (1)
a12 = 2(12)+16-a
a12 = 24+16 -a
a12= 40 - a
i hope it will help u
NeelamG:
i hope it will be helpfull
Similar questions