Step-by-step explanation:
al nth term:
numerator:
denominator:
so nth term :
b). 1; 11; 27; 49
first difference: 10; 16; 22
second difference :6
formula for 1st difference:3a+b
formula for 2nd difference:2a
Therefore:
2a=6
a=3
3a+b=10
sub in a
3(3)+b=10
9+b=10
b=1
sub into quadratic formula
So Tn: