Question

If sum of n terms of an A.P. is n'+5n then find general term.
a) n+1
b) 2n+4
c) 3n
d) n²+3n ​

Answer 1

Answer:

Putting n=1, 5n

2

−3n

=5−3=2

putting n=2, 5n

2

−3n

5×2

2

−3×2 =14

therefore 2nd term is 14−2=12

therefore A.P is 2,12,22.... and so on.

10th term =a+9d

=2+9×10

=2+90

=92.

Answer 2

sorry I can't know the answer