Find the units digit of the expression 4137^743.
The pattern followed by the units digit of multiples of 7 is 7, 9, 3, 1, 7, 9, 3, 1.............
So, the units digit get repeated after every fourth power.
Now, 743 = 740 + 3
= 4 × 185 + 3
So, the units digit for 740th power will be 1.
For 741th power, it will be 7.
For 724th power, it will be 9.
For 743th power, it will be 3.
Thus, the units digit of the number 4137743 will be 3.