## Ash90 one year ago simplify the expression (x^2-10x+25)^1/2

1. Ash90

i have (x-5)^2=((x-5)^2)1/2=(x-5) then i do [5, infinity) but the answer is wrong

2. goformit100

Use multinomial theorem.

3. hartnn

simplified form is x-5

4. hartnn

u need domain ?

5. Ash90

i have x-5 and for my domain answer i put...

6. Ash90

|dw:1389459862624:dw|

7. Ash90

or should it be...

8. hartnn

why ?? why can x not be less than 5 ?

9. Ash90

|dw:1389459912753:dw|

10. hartnn

whats the domain of x-5 ?

11. hartnn

what if x= 3 is that allowed value ?

12. hartnn

note that x-5 does not place any restrictions on x

13. ParthKohli

The simplified form is |x - 5|.

14. ParthKohli

The domain of that should be all real numbers. x^2 - 10x + 25 is always positive, so you can input everything.

15. Ash90

so 5

16. ParthKohli

No, (-infty,infty)

17. Ash90

yes everything like -infinity to positive infinity

18. ParthKohli

Yup.

19. Ash90

oh see i had the left with a bracket so that was wrong

20. Ash90

thanks

21. ParthKohli

Do you need the range as well?

22. Ash90

after i had messed it up i just started guessing

23. Ash90

let me see..

24. Ash90

yeah i think so

25. ParthKohli

OK, so the simplification is |x - 5|. Do you know what the range of any absolute value function is?

26. Ash90

the range would be [5, positive ) right?

27. hartnn

nopes, the range of |x| is x>=0