Question

If $x$ is a whole number, than $x^2(x^2-1)$ is always divisible by

• A. $24$
• B. $12-x$
• C. $12$
• D. $12(x-1)$

Answer 1

The correct option is C $12$

By hit and trial method
$x=0,x^2(x^2-1)=0$
$x=1,x^2(x^2-1)=0$
$x=2,x^2(x^2-1)=12$
$x=3,x^2(x^2-1)=72$
Hence, $x^2(x^2-1)$ is always divisible by $12.$