Solution:
The difference of cubes identity is
if a and b are any two real numbers, then difference of their cubes, when taken individually:
a³-b³= (a-b)(a² + ab + b²)→→→Option (D) is
true option.
I will show you, how this identity is valid.
Taking RHS
(a-b)(a² +b²+ab)
= a (a² +b²+ab)-b(a² +b²+ab)
= a³ + a b² +a²b -b a² -b³-ab² Cancelling like terms, we get
= a³-b³
= LHS
