## anonymous one year ago Find the domain f(x)=(x+2)/(x^2-1)

1. Astrophysics

You're looking at the restrictions, so where the denominator is = 0, so solve for $x^2 - 1 = 0$

2. anonymous

$\pm1$

3. anonymous

i got that part. i don't exactly know how to write it in interval notation tho

4. anonymous

($-\infty,-1]\cup(0,1]\cup(1,\infty)$

5. anonymous

i don't think i did it right

6. Astrophysics

You could write it as such $( - \infty, - 1) \cup (1, \infty)$ because open bracket implies it's not included, a square bracket means, it would be included in the domain.

7. Astrophysics

of course I forgot 0 xD

8. Astrophysics

But you get the point right?

9. UsukiDoll

I used to hate those write in set notation or interval notation parts to the question because I got confused with ( and ]. This was before OpenStudy popped up.

10. Astrophysics

Yeah I can't remember last time I even used interval notation to be honest

11. UsukiDoll

College Algebra had truckloads... but the thing is it doesn't appear again afterwards.

12. Astrophysics

Yea, I used it in calculus 1, then never saw it again haha...

13. Astrophysics

|dw:1434430709134:dw| so this is how it looks like in a number line (random example) $(- \infty, -1/2] \cup [3, \infty)$ I think this will make it clear on what exactly is going on.

14. Astrophysics

|dw:1434430860916:dw|

15. anonymous

thanks this is going to help a lot for the rest of my hw

16. Astrophysics

No problem :)