Question

Factor each Polynomial. Show your work. Solve using
Difference of Squares: A^2 - B^2 = (a -b) (a + b)
Differences of Cubes:
A^3 - B^3 = (A - b) (a^2 + ab + b^2)
Sum of Cubes:
A^3+ B^3 = (a + b) (a^2 - ab + b^2)

12. 5x^3 - y^3

Answer 1

Well this is a difference of cubes\[5x ^{3}-y ^{3}\]=\[=(x(\sqrt[3]{5})-y)((x ^{2}5^{2/3})+(xy \sqrt[3]{5})+y ^{2})\]

Answer 2

you just have to leave the 5 as a root 3

Answer 3

just start easy on me

Answer 4

your difference of cubes is misleading and not clear. it is actually

Answer 5

I just started the problem duh and that's what I got so far

Answer 6

\[(x ^{3}-y ^{3})=(x-y)(x ^{2}+xy+y ^{2})\]

Answer 7

yes

Answer 8

(5x - y) is what I have so far; what's next?

Answer 9

the x^3 in this problem is 5x^3 when you cube root that, it becomes \[x(\sqrt[3]{5})\]

Answer 10

you cube root the whole thing, not just the x

Answer 11

I can't root the x in the calculator, I can cube the 5, but it gives me a decimal 1.709975947

Answer 12

so you just leave it in cube root form like I did.

Answer 13

we put it in the calculator like that, but we don't write it on our paper

Answer 14

so where do I go from (5x - y)

Answer 15

that's is the wrong step. you can't just ignore the 5 and only cube root the x and y

Answer 16

what is it 5(x - y)

Answer 17

why do you need to put that into the calculator?

Answer 18

idk what ya mean

Answer 19

you said you put it into the calculator and don't write it on paper right?

Answer 20

cause we don't nee to write it on our paper; if it's in the calculator

Answer 21

so what's my next step

Answer 22

you need to cube root 5x^3 and y^3 put into the form (a-b)

Answer 23

where 5x^ is a^3 and y^3 is b^3

Answer 24

x and y ^3 will be x and y, so what about the 5