Question

if sn= n(n+8),find T1 and Tn​

Answer 1

Answer:

9

Step-by-step explanation:

sn=n(n+8) so Tn=n(n+8)

T1=1(1+8)

   =1*9

   =9.

Answer 2

Answer:

Sn = n(n+8),

S1= T1= 1(1+8) = 1(9)= 9

T2= 2(2+8) = 2(10) = 20

d= T2 - T1 = 20-9 = 11

Tn = a+(n-1)d

= 9+(n-1)11

= 9+11n-11

= 11n-2