## osanseviero 3 years ago I need to find the natural domain of:

1. osanseviero

$\frac{ x }{ \sqrt{-x ^{2}-x+2} }$ Can someone see if it is this?: |dw:1382585115287:dw|

2. osanseviero

I think I am wrong :/

3. anonymous

Domain is -2 < x < 1.

4. osanseviero

shouldnt -2 and 1 be included?

5. anonymous

You want to make sure that what is in the square root, namely -x^2 - x + 2 > 0. Solving that quadratic inequality, yields -2 < x < 1.

6. anonymous

NO! when x = -2 and x = 1, the denominator will equal 0, wjich is undefined!

7. osanseviero

Right! just noticed that! thanks

8. anonymous

welcome.

9. osanseviero

:)

10. anonymous

practice solving -x^2 - x + 2 > 0

11. anonymous

to makes ure you get -2 < x < 1

12. anonymous

sure*

13. osanseviero

Just did it, thanks :)

14. anonymous

cool.