Decomposing a number into its prime factors is like taking an engine apart to see its elementary pieces. This technique will also be useful later on, when we work with polynomials.

Definition — Decomposition into prime factors

Every natural number n>1n > 1 can be written in a unique way (up to order) as a product of prime factors (Fundamental Theorem of Arithmetic).

The uniqueness of the decomposition is the property that makes factorisation a reliable tool: we will return to it in the form of a theorem later on.

Topics: Numbers and operations
Concepts: Prime factorisation · Prime number · Fundamental theorem of arithmetic
Skills: Decomposing