Question

How do you expand `(y-x^2)^3`?

Answer 1

`y^3-3x^2y^2+3x^4y-x^6`

Explanation:

You can expand by using the identity:

`(a+b)^3=a^3+3a^2b+3ab^2+b^3`

So, in this case, it is:

`(y-x^2)^3=y^3+3y^2(-x^2)+3y(-x^2)^2+(-x^2)^3`

`=y^3-3x^2y^2+3x^4y-x^6`