Author Topic: Need help on algebra 2 homework  (Read 2479 times)

Spaced out during todays lesson, its on Sum of Cubes and Difference of Cubes.
Ex.) Factor x^3-1000
« Last Edit: November 16, 2009, 08:44:44 PM by Chewy »


LOL
factoring? seriously?
pfffffffft

I think I found it out but the formula is (a^3 -b^3)=(a-b)(a^2+ab+b^2)
« Last Edit: November 16, 2009, 08:45:14 PM by Chewy »


This can't be factored.  Unless you are using imaginaries to do it, it's unfactorable.
« Last Edit: November 16, 2009, 08:38:45 PM by DrMobius »



I think I found it out but the formula is (a[3] -b[3])=(a-b)(a[2]+ab+b[2])

Right.

Quote
This can't be factored.  Unless you are using imaginaries to do it, it's unfactorable.

Wrong.

What?
But i got (x-10)(x^2+10x+100)
That right?
yus.
and you can use the ^ key :D

Ok now different kinds of problems
Ex.) Solve x^3-27=0

Ok now different kinds of problems
Ex.) Solve x^3-27=0

Difference of 2 cubtes
a=x
b=3

Wrong.
Fair enough.  Even so, too of its zeros are imaginary.  That is what forgeted me up I guess.  the zeros to a2 + ab + b2 are both at imaginary numbers. 
« Last Edit: November 16, 2009, 09:04:11 PM by DrMobius »

I understand it all now the answer to x^3-27=0 is x=3, -3+-3i sqrt3/2
or x equals three and negative three plus or minus three i times the square root of three over two

I understand it all now the answer to x^3-27=0 is x=3, -3+-3i sqrt3/2
or x equals three and negative three plus or minus three i times the square root of three over two

(x-3)(X^2+3x+6)
« Last Edit: November 16, 2009, 09:11:34 PM by FlyGuy45 »