Actually, this is a difference of cubes, so you use the difference of cubes formula:
So in
,
let a = 5 and b = 3u, so
01
Hello Everyone,
I'm returning to school after a long time off, and I know this is a pretty basic question, but I can't seem to get it.
The problem is pretty simple:
Factor Completely
125-27u^3
Now I know that the cube of 125 is 5 and the cube of 27 is 3, and I'm sure that ties into here since it sounds like I need to find the GCF twice and make three parentheticals. I can't seem to make this work however, and I'm feeling foolish.
Many Thanks!
I think you mean that the cube of 5, 5^3, is 125 and that the cube of 3, 3^3, is 27...?
You only need to apply the difference-of-cubes factoring formula to what is, as you have noted, equivalent to (5)^3 - (3u)^3.
You should end up with two sets of parentheses....
sum difference cubes
Using ye olde Google