Question

Factor x^4 + x y^3 + x^3 + y^3 completely.

Answer 1

Why do I think this is one of those odd candidates for "Grouping"?

x^4 + x y^3 + x^3 + y^3

x^4 + x^3 + x y^3 + y^3

(x^4 + x^3) + (x y^3 + y^3)

(x^3)(x + 1) + (y^3)(x + 1)

Now what?

Answer 2

Yes, its factor by grouping. Is that the answer?

Answer 3

@tkhunny

Answer 4

You didn't answer my question. Keep factoring!