Question

Factorise $32a^4-8a^2$

• A. $8a(2a+1)(2a-1)$
• B. $4a^2(2a+3)(2a-1)$
• C. $8a^2(2a+1)(2a-1)$
• D. $8a^2(2a+1)\left(2a\right)$

Answer 1

The correct option is C

$8a^2(2a+1)(2a-1)$

Given
$32a^4-8a^2$
Taking $8a^2$ common ,we get
$8a^2(4a^2-1$)
$8a^2\left(\right(2a{)}^2-1$)
Using $a^2-b^2=(a+b)(a-b)$ ,we get

Taking a = 2a and b = 1, we have
$8a^2(2a+1)(2a-1)$