Question

how to simplify y^3-w^3

Answer 1

You have to memorize this formula
Write each term as ( )^3 so we have y and w
(y - w)(y^2 + yw + w^2) Here is how it is done.

( )^3 - ( )^3
(y)^3 - (w)^3
take what is in the parentheses and use the sign in the problem
(y - x)
Take what is in the first ()'s and square it
y^2
Put the opposite sign of the problem
+
Multiply what is in both parentheses
yx
Always put a + sign
+
Square what is in the last parentheses
y^2

SO
(y - x)(y^2 + yx + x^2)

Answer 2

I'm not sure that the factored form is technically "simplier"