Question

a4-2a2b2+b4factorise

Answer 1

(a^2)^2-2a^2b^2+(b^2)^2
(a^2-b^2)^2
(a^2-b^2)(a^2-b^2)

Answer 2

a4 - 2a2b2 + b4 = 0
[ a2 - b2 ] ^2 = 0  ..........since x2 - 2xy + y2 = [ x - y] ^2
[ a2 - b2 ] [ a2 - b2] = 0
[ a + b] [a - b] [ a + b] [a -b] =0