andypanda
Nov 29, 2006, 04:20 PM
I have a few questions concerning functions...
1) X^3+64
2) 54p^3-16q^3
3) 2x^2-5x=3
4) 2x^2-8x=0
:confused: :confused:
worthbeads
Nov 29, 2006, 04:43 PM
What exactly are you having trouble with?
galactus
Nov 30, 2006, 07:59 AM
I have a few questions concerning functions...
1) X^3+64
2) 54p^3-16q^3
3) 2x^2-5x=3
4) 2x^2-8x=0
:confused: :confused:
It appears you want to factor.
The first one is the sum of 2 cubes... Easy.
3 and 4 are completing the square.
The 2nd one is the difference of 2 cubes, but a little trickier. I'll do it and you try the others.
54p^3-16q^3
Factor out 2:
2(27p^3-8q^3)
Make into a difference of cibes inside the parentheses:
2((3p)^3-(2q)^3)
Now, let x=3p and y=2q:
2(x^3-y^3)
Difference of cubes formula:
2(x-y)(x^2+xy+y^2)
Resub:
2(3p-2q)((3p)^2+(3p)(2q)+(2q)^2)
2(3p-2q)(9p^2+6pq+4q^2)
Does that help?