[tex]\\ \rm\longmapsto a^3-a+b^3-b[/tex]
[tex]\\ \rm\longmapsto a(a^2-1)+b^3-b[/tex].
Take out b common
[tex]\\ \rm\longmapsto a(a^2-1)+b(b^2-1)[/tex]
[tex]\\ \rm\longmapsto (a+b)(a^2-1)(b^2-1)[/tex]
Step-by-step explanation:
a^3-a+b^3-b = a³+b³-a-b
= a³+b³ - (a+b)
= (a+b)(a²-ab+b²) - (a+b)
= (a+b) (a²-ab+b²-1)
