Question

(x^3-8) is factored to
(x-2)(x^2+2x=2) can someone explain this, or give me the formula to do a similar problem

Answer 1

google a^3-b^3 formula

Answer 2

why the b^3, the problem only has one exponent

Answer 3

http://www.purplemath.com/modules/specfact2.htm

Answer 4

observe that 8 = 2^3

Answer 5

\[a^3-b^3 = (a-b)(a^2+ab+b^2)\]

Answer 6

x^3-8 = x^3-2^3

Answer 7

this x^3-8 = x^3-2^3 is the same as (x-2)(x^2+2x=2

Answer 8

correct

Answer 9

@Hero Let's try to arrive at the solution purely.
Seems intricate.

Answer 10

It is easy to see right, just 6 terms out of which 4 cancel out when you expand.
you looking for derivation of formula ?

Answer 11

@rsadhvika

Answer 12

yeah ?

Answer 13

Can someone post this as a new question? How to prove it.

Answer 14

x^n-y^n = ... that proof you want ?

Answer 15

Yes. For this case where n = 3.

Answer 16

I'm working on it, but I'd like to see what others have.

Answer 17

im doing the same right now, trying to understand the proof

Answer 18

@Hero Got it.