For example, in the algebraic expression 5xy + 3x the term 5xy has been formed by the factors 5, x and y, i.e.,
5xy = x y
Observe that the factors 5,x and y of 5xy cannot further be expressed as a product of factors. We say that 5 , x and y are ‘prime’ factors of 5xy. In algebraic expressions, we use the word ‘irreducible’ in place of ‘prime’.
Next consider the expression 3x (x + 2). It can be written as a product of factors. 3, x and (x + 2)
`3x(x + 2) = 3 × x × (x + 2) `
The factors 3, x and (x +2) are irreducible factors of 3x (x + 2).