# Math Help - trinomial

1. ## trinomial

this is confusing. how do you expand this, any tips on how to expand trinomials??

x^3 + 8

2. Originally Posted by algebra2
this is confusing. how do you expand this, any tips on how to expand trinomials??

x^3 + 8

If you mean factor notice that this is the sum of cubes

$x^3+2^3=(x+2)(x^2-2x+4)$

I hope this helps.

Good luck.

3. could you explain it a bit

4. Originally Posted by algebra2
could you explain it a bit

This is a formula that should be memorized

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

$x^3+8=x^3+2^3$
$x^3+2^3=(x+2)(x^2-2x+4)$