First slide

Binomial theorem for positive integral Index

Question

If $a_{n} = 2^{2^{n}} + 1$ , then for $n > 1$ last digit of $a_{n}$ is

Moderate

A

5
B

7
C

3
D

4

Solution

For $n = 2, a_{n} = 2^{4} + 1 = 16 + 1 = 17$ . Assume that $a_{k} = 2^{2^{k}} + 1 = 10 m + 7$ where $k > 1$ and m is some positive integer.

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App