Question

The sum of n terms of an ap is 5n^2-3n find the ap and also its 10th term

Answer 1

Sn = 5 n^2 - 3n

we know that
Tn = Sn - Sn-1

so

Tn = 5n^2 -3n - 5 (n-1)^2 +3(n-1)

= 10n - 5

now

T10 = 10×10-5
=95