Explain Interval notation

Let us study what is Interval notation,

An interval can be shown using set notation. For instance, the interval that includes all the numbers between 0 and 1, including both endpoints, is written 0 ≤ x ≤ 1, and read "the set of all x such that 0 is less than or equal to x and x is less than or equal to 1."

The same interval with the endpoints excluded is written 0 <>

Replacing only one or the other of the less than or equal to signs designates a half-open interval, such as 0 ≤ x <>intervals. In this notation, a square bracket is used to denote an included endpoint and a parenthesis is used to denote an excluded endpoint. For example, the closed interval 0 ≤ x ≤ 1 is written [0,1], while the open interval 0 <: x <>
I hope the above explanation was useful, now let me explain Factorisation.