Find last digit of a Number

Base/Power	1	2	3	4
1	1	1	1	1
2	2	4	8	6
3	3	9	7	1
4	4	6	4	6
5	5	5	5	5
6	6	6	6	6
7	7	9	3	1
8	8	4	2	6
9	9	1	9	1

                                                       Base/Power Table

This is the Base/Power table to find last digit of a number. A power of 4 will be iterative after it all pattern will repeat, so we are taking only 4 power value.

There are few steps to find:

Let any number is a^b

Step 1: Find remainder of b by 4

Ex: c=b%4

Step 2: Find the last digit of base number.

i.e: a=243 then last digit of number will be d=3

Step 3: Now find value in Base/Power table of d/c. This value will be your final answer.

Practice

Find the last digit of (135843)²⁴⁵⁸⁶.

Solution

According to Assumption a=135843 and b=24586

Step 1: c=24586%4, c=2

Step 2: d=3

Step 3: in Base/Power table d/c or 3/2 will be 9.

So, finally the last digit of (135843)²⁴⁵⁸⁶ will be 9.