Domain of this function:-

y =|x

The basic factorial function has the specific form y equals x factorial. The function x factorial is the operation of multiplying the variable x times (x minus one) times (x minus two) times (x minus three) etc. until it reaches the final integer one. In other words, it is the multiplication of all the integers starting at one, the natural numbers, up to the x value. Any non-integer x is rounded down to the integer form. The factorial of zero is one by definition. The factorial function has a limited domain for the x variable which is the set of all real numbers where x is greater than or equal to zero. The range of the factorial function is a specific set of integers greater than zero: 1, 2, 6, 24, 120, 720 . . . It is still an infinite set.