Question

If the sum of n term of an A.P is 3n2+5n find its 27th term

Answer 1

Answer:

Sn=3n2+5n

s1 = 3+5=8

s2 = 12 +10=22

S3=27 +15=42

Ap=8,14, 20...:

a=8,d=6

a27=8+(27-I) 6

a27=8+26x6

a27=8+156=164. Ans.