## anonymous one year ago f(x) = x2 - 16 and g(x) = x+4. Find F over G of and its domain

1. anonymous

$\frac{ f(x) }{ g(x) }$ is this what you mean?

2. anonymous

yeah

3. anonymous

$\frac{ (x^2 -16) }{ (x+4) }$ you can factor the numerator in a way so as to get two expressions one of which will be (x+4) which will cancel out with the denominator

4. anonymous

so in other words (x+4)(?) = (x^2 - 16)

5. anonymous

4x and 16x^2 right

6. anonymous

im sorry i don't quite understand your expression can you write it out?

7. anonymous

im not getting it

8. anonymous

okay do you know how to factor $(x^2-16)$

9. welshfella

x^2 - 16 is the difference of 2 squares x^2 is a perfect square and so is 4

10. welshfella

have you factored something like that before?

11. anonymous

no

12. anonymous

are you familiar with the difference of squares method (its the way to factor expresions like these )

13. anonymous

yeah but its a real number right

14. anonymous

basically it means that if your constant (in this case the 16) is a perfect square you can factor the expression by multiplying two expressions which's constant is the perfect square of your original constant

15. anonymous

okay im over complicating this XD

16. anonymous

okay do you know what $\sqrt{16} = ?$

17. anonymous

2*8

18. anonymous

umm no , what number squared equals 16

19. anonymous

256

20. anonymous

no thats 16 squared

21. welshfella

no what number when multiplied by itself equals 16 like 3 * 3 = 9 So 3 is the square root of 9.

22. anonymous

4

23. welshfella

right

24. anonymous

correct which means that $\sqrt{16} = 4$ and because 4 is a whole number we call 16 a perfect square

25. anonymous

okay thanks