Question

x^3-729

factor the difference of the two cubes

Answer 1

(a^3 - b^3)

(a-b)(a^2-ab+b^2) ?

Answer 2

i am lost

Answer 3

what is the cuberoot of 729?

Answer 4

ummm

Answer 5

9....got it;

(x-9)(x^2 +9x +81)

or is it...

(x-9)(x^2 -9x +81)

one or the other, I forget which :)

Answer 6

its the first one

Answer 7

hey... i just figured that out :)

Answer 8

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

Answer 9

yep.... learned it like 4 semesters ago and havent used it since :/

Answer 10

i always remember that is one or the other, but then i think if i set this =0 and solve for x, I would get x=9 so one of the factors is x-9 since x-9=0