Question

solve this it is of 2 marks

Answer 1

Given:-
a1=a
a2=b
an=2a
n=?

d=a2-a1
=b-a

by using formula,
=>an=a+(n-1)d

2a=a+(n-1)(b-a)
2a=a+bn-an-b+a
2a=2a+bn-an-b
2a-2a=bn-an-b
0=(b-a)n-b
b=(b-a)n
b/(b-a)=n

the term is=b/(b-a)