Question

what is 1+1=?
and then what is last digit of $7^{45}$

Answer 1

if mathamatically then2 and if  logically then its 11. u can calculate it by measuring 7, 45 times.

Answer 2

The all powers of 7 is and it contains the last values as 7,9,3,1 so the by taking the power % 4 we get 1 so the last power of 7^45 is 1. The 4 comes from the 4 values of powers of 7. i dont know in what way your asking 1+1= anyway it is by math 2