- Home
- Standard 9
- Mathematics
2. Polynomials
easy
Factorise :
$a^{3}-2 \sqrt{2} b^{3}$
Option A
Option B
Option C
Option D
Solution
$a^{3}-2 \sqrt{2 b^{3}}=(a)^{3}-(\sqrt{2} b)^{3}$
$=(a-\sqrt{2} b)\left\{(a)^{2}+(a)(\sqrt{2} b)+(\sqrt{2} b)^{2}\right\}$ $\left[\because a^{3}-b^{3}=(a-b)\left(a^{2}+a b+b^{2}\right)\right]$
$=(a-\sqrt{2} b)\left(a^{2}+\sqrt{2} a b+2 b^{2}\right)$
Standard 9
Mathematics