## anonymous one year ago Identify the domain and range and sketch the graph of the function y=-sqrt-x

1. anonymous

$y=\sqrt{-x}$

2. anonymous

$y=-\sqrt{-x}$

3. anonymous

you can't take the square root of a negative number , solve $-x\geq 0$ in one step to get the domain

4. anonymous

same domainfor $$y=-\sqrt{-x}$$makes no difference

5. anonymous

as for the range, the square root is greater than or equal to zero, so minus the square root will be less than or equal to zero

6. anonymous

Ok so the domian would be (-infinity, infinity)?

7. misty1212

HI!!

8. misty1212

and no

9. misty1212

do you know how to solve $-x\geq 0$ for $$x$$?

10. anonymous

No

11. misty1212

if not, that is fine, i will show you

12. anonymous

Ok thanks

13. misty1212

ok change the sign, and flip the inequality

14. anonymous

Ok

15. misty1212

the math teachers call it "multiply by $$-1$$" or sommat, but you just make it positive and change greater than or equal to to less that or equal to

16. anonymous

what @misty1212 said

17. anonymous

don't you divide by -1 and flip the sign?

18. misty1212

lol multiply by -1, divide by -1, potato potahto

19. anonymous

ok so would the domain be -1?

20. misty1212

ooooh kay lets go slow

21. misty1212

the domain is an interval right? not a number

22. anonymous

Yes

23. misty1212

the question is, what interval is it now we know that you cannot take the square root of a negative number, so the input has to be positive right?

24. misty1212

the input in this case is $$-x$$ in english we would say that $$-x$$ must be greater than or equal to zero in math write $-x\geq 0$

25. misty1212

to solve that for $$x$$ change the sign so that it is $$x$$ instead of $$-x$$ and change the inequality as well

26. misty1212

i.e $-x\geq 0\iff x\leq 0$ and that is your domain

27. misty1212

if you want to write it as an interval that works too, call it $\huge (-\infty, 0]$

28. anonymous

Ok so what would the range be?

29. misty1212

ok again we go slow the range is all possible outputs the square root is always greater than or equal to zero you have a minus sign in front, so that means the range will be all numbers less than or equal to zero

30. anonymous

Ok so how would I graph it?

31. misty1212

if you want to write it as an interval, write it the same as the domain in this case they are the same

32. misty1212

how to you graph $$y=-\sqrt{-x}$$?

33. misty1212

is that the question?

34. anonymous

Well I have to sketch the graph of the function

35. anonymous

do you know what $$y=\sqrt{x}$$ looks like?

36. anonymous

No

37. anonymous

hmm then you can't really do it maybe look it up

38. anonymous

ok

39. anonymous
40. anonymous

ok be very careful here

41. anonymous

wolfram has given you too much information

42. anonymous

where it says "complex valued plot" change it to "real valued plot"

43. anonymous

Oh ok thanks

44. anonymous

|dw:1440985596594:dw|you should see something like that