Question

Help me simply this??
x^3-125

Answer 1

Use the fact that x^3 + y^3 = (x + y)*(x^2+y^2-xy), so x^3 - 125 = x^3 + (-5)^3 = (x-5)*(x^2-5x+25).

Answer 2

Where did the y come from?

Answer 3

i thinks it is o

Answer 4

??????

Answer 5

Here are the formulas you will need to use:
x^3 - y^3 = (x-y)(x^2 +xy +y^2)
x^3 + y^3 = (x+y)(x^2 -xy +y^2)

1) x^3 - 125 is a difference of two cubes.
x^3 - 125 = x^3 - 5^3 = (x-5)(x^2 + 5x + 25)

2) x^3 + 8y^3 is a sum of two cubes
x^3 + 8y^3 = x^3 + (2y)^3 = (x+2y)(x^2 - 2xy + 4y^2)

Answer 6

You just copy and pasted that from yahoo answers....

Answer 7

I don't understand where the 5^3 comes from... There has to be an easier way to do this rather than using a formula...

Answer 8

There isn't. :/ Use wolfram alpha if it helps

Answer 9

Then there must be an easier way to explain it?

Answer 10

In general-
Difference 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)

1) Using the difference of cubes, (a=x, b = 5) we get (x-5)(x^2+5x+25)
2. Using the sum of cubes, (a=x, b = 2y) we get (x+2y)(x - 2xy + 4y^2)

Hope this helps!

Answer 11

Dude just quit copy and pasting yahoo answer crap, I've already been to all of those

Answer 12

x^3-125=0
x^3=125
x^3=5^3

this is the correct answer