What is the unit digit in 7^105 ?1579

The unit digit of 7^105 can be found by understanding the pattern of the unit digit of powers of 7.

The unit digit of 7^1 is 7. The unit digit of 7^2 is 9. The unit digit of 7^3 is 3. The unit digit of 7^4 is 1. After this, the unit digit repeats every 4 powers.

So, to find the unit digit of 7^105, we need to find the remainder when 105 is divided by 4.

105 divided by 4 gives a remainder of 1.

Therefore, the unit digit of 7^105 is the same as the unit digit of 7^1, which is 7.