Factorisation

[aznboy50]

If this came up in an exam, I wouldn't be able to factorise the numerator just by looking at it.

Can someone please explain what I should look for etc etc when factorising this and any general tips on factorisation.

Thank you for the help!

[aznxD]

Factorise by grouping two and two.

(a^3-ab^2)+(a^2b-b^3)
a(a^2-b^2)+b(a^2-b^2)
(a+b)(a^2-b^2)

[TrueTears]

numerator: a^2(a+b)-b^2(a+b) = (a+b)(a^2-b^2)

to see this clearer let u = a+b

[aznboy50]

Factorise by grouping two and two.

(a^3-ab^2)+(a^2b-b^3)
a(a^2-b^2)+b(a^2-b^2)
(a+b)(a^2-b^2)

numerator: a^2(a+b)-b^2(a+b) = (a+b)(a^2-b^2)

to see this clearer let u = a+b

Thank you. Very helpful

[nacho]

I see we have a terence tao fan. (Y)