The unit digit in $$(743)^{85} −(525)^{37} + (987)^{96}$$ IS ________

The unit digit in $$(743)^{85}$$ = 3 (since the cyclicity for powers of numbers with unit digit 3 is 4)

The unit digit in $$(525)^{37}$$ = 5 

The unit digit in $$(987)^{96}$$ = 1 (since the cyclicity for powers of numbers with unit digit 7 is 4)

The unit digit of $$(743)^{85} −(525)^{37} + (987)^{96}$$ will be = (.......3) - (.......5) + (.......1)

Now, (3-5+1) will give us a negative number, thus we will take a carry from the second last digit of the first number.

Therefore, the unit digit will be = 13 - 5 + 1 = 9