Question

Find the 4th term Thank you in advance

Answer 1

B1 = 2
b2 = (b1)^2 + 1 = 2^2 + 1 = 5
b3 = (b2)^2 + 1 = 5^2 + 1 = 26

b4 = (b3)^2 + 1 = 26^2 + 1 = 676+1=677

Answer 2

So you start off with the given information:
$b_{1}$ = 2
$b_{n}$ = ($b_{n-1}$)² + 1

Since you're looking for the 4th term, that would mean that you are looking for $b_{4}$.
Since you know that we are looking for when n = 4, you can start with what we started off with, which is n = 1, to get to where n = 4.
When n = 1, b = 2,
when n = 2, b = 3,
when n = 3, b = 4,
when n = 4, b = 5.

So the fourth term, when n = 4, is 5.