Question

Factorise : $27+125a^3+135a+225a^2$

• A. $(3+5a)(3+5a)(3-5a)$
• B. $(3-5a)(3-5a)(3+5a)$
• C. $(3+5a)(3+5a)(3+5a)$
• D. $(3-5a)(3-5a)(3-5a)$

Answer 1

The correct option is C $(3+5a)(3+5a)(3+5a)$

$27+125a^3+135a+225a^2$
$={\left(3\right)}^3+{\left(5a\right)}^3+3\times 3^2\times 5a+3\times 3\times {\left(5a\right)}^2$
$={(3+5a)}^3$