if the sum of first n terms of an AP is given by Sn=3n^2+2n , find the nth term of the AP.
(plzz give the solution also)
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sn =3n²+2n
a1 = s1 = 3*1+2*1 = 5
s2 = 3*2²+2*2 = 12+4 =16
s3 = 3*3²+2*3 = 27+6 =33
a2 = s2-s1 = 16-5 =11
a3 = s3-s2 =33-16 =17
therefore
5,11,17, ....are terms in ap
a=5 ,
common difference (d) = a2-a1 =11-5 =6
nth term =an = a+(n-1)d
= 5+(n-1)6
=5+5n-6
=5n-1
a1 = s1 = 3*1+2*1 = 5
s2 = 3*2²+2*2 = 12+4 =16
s3 = 3*3²+2*3 = 27+6 =33
a2 = s2-s1 = 16-5 =11
a3 = s3-s2 =33-16 =17
therefore
5,11,17, ....are terms in ap
a=5 ,
common difference (d) = a2-a1 =11-5 =6
nth term =an = a+(n-1)d
= 5+(n-1)6
=5+5n-6
=5n-1
mysticd:
ur welcome
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