+66 Completely factor 27x3 - 512y3
AND
Completely factor 4x2-9y2
I am having issues with these certain problems. Please explain if possible how to do this. I want to figure it out but it's not on any of my lessons that the teacher has released.
Hello KaylaDoodlez,
For the first one:
27x3−512y3
If you want "Binomial factoring"
Then there is no common factor for 27 and 512
Thus factoring it by a common factor isn't possible.
There is a formula for this:
a3+b3=(a+b)(a2−ab+b2)
a3−b3=(a−b)(a2+ab+b2)
We will use the second one as it is similar to your question "Difference between the two cubics"
(3x−8y)(9x2−24xy+64y2)
Second question:
Difference between squares.
a2−b2=(a+b)(a−b)
4x2−9y2=(2x−3y)(2x+3y)
hope that helped, you really need to memorize the formula and have practice!
