Math Is Fun Forum

mathxyz

Member

From: Brooklyn, NY

Registered: 2024-02-24

Posts: 1,053

Factor Sum of Cubes

Factor x^3 + 125. This is found on page 57 number 34.

Let me see.

I will use formula 6 on page 44.

(x + a)(x^2 - ax + a^2)

Let 125 be 5^3.

I now have x^3 + 5^3.

Let a = 5

x^3 + 5^3 = (x + 5)(x^2 - 5x + 5^2)

x^3 + 5^3 = (x + 5)(x^2 - 5x + 25)

You say?