Question 451706: Factor: x^3-8
I got the answer (x-2)(x^2+2x+4) but I don't know how
Please show me step by step to get the answer. thanks Found 2 solutions by Alan3354, solver91311:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! How did you get the answer, if you don't know how? Do you mean the answer was given?
-----------
It's a difference of 2 cubes.
If you remember one factor is a-b, you can divide it to find the other.
---------
PS The sum of 2 cubes, a^3 + b^3 is similar to the difference above
Use the factorization of the difference of two cubes:
And recall that .
For future reference, you can remember the sum and difference of two cubes thusly:
Use the mnemonic "San Diego Padres" to remember "Same sign, Different sign, Plus sign" to help you know which signs to put into the right hand side of the equation.
John
My calculator said it, I believe it, that settles it
