what is the units digit of ( 44 ^ 4 ) ( 33 ^ 5 ) ( 21 ^ 6 ) ?
"the units digit of 44 ^ 4 is the units digit of 4 ^ 4 which is 6 . the units digit of 33 ^ 5 is the units digit of 3 ^ 5 which is 3 . the units digit of 21 ^ 6 is the units digit of 1 ^ 6 which is 1 . the units digit of 6 * 3 * 1 is 8 . the answer is e ."
divide(add(multiply(factorial(44), factorial(4)), multiply(factorial(44), factorial(5))), 44)