Question

Question 4(v)
Factorise
$a^4-2a^2{b}^2+b^4$

Answer 1

$a^4-2a^2{b}^2+b^4=(a^2{)}^2-2(a^2\left)\right(b^2)+(b^2{)}^2=(a^2-b^2{)}^2=[(a-b)(a+b){]}^2=(a-b{)}^2(a+b{)}^2$