3psilon 2 years ago If complex number z = 4-6i , then | z-2 | = ?

1. UnkleRhaukus

|dw:1350784902834:dw|

2. 3psilon

I don't understand?

3. UnkleRhaukus

|dw:1350784964700:dw|

4. 3psilon

Why is it coordinates? I thought it meant absolute value?

5. UnkleRhaukus

|dw:1350785015499:dw|

6. UnkleRhaukus

the absolut value is the length of the vector

7. 3psilon

So it is just Square root of 36+16?

8. UnkleRhaukus

|dw:1350785068730:dw|

9. 3psilon

or 4 i mean

10. UnkleRhaukus

almost

11. UnkleRhaukus

the length of z is Square root of 36+16 but we want the length of z-2

12. UnkleRhaukus

yeah so how long is z-2?

13. UnkleRhaukus

(tha answer is an irrational number )

14. satellite73

i am a bit lost \(z=4-6i\) so \(z-2=2-6i\) pythagoras gives the length

15. 3psilon

Okay I got cha! Thanks @UnkleRhaukus !

16. UnkleRhaukus

what answer did you arrive at?

17. 3psilon

Root 40

18. UnkleRhaukus

good work, can you simplify √40?

19. 3psilon

2 root 10?

20. UnkleRhaukus

good show

21. 3psilon

:) thx a lot

22. UnkleRhaukus

if you can remember the distance formula as the square root of the sums of the squares of the differences of the corresponding coordinates , thats great, otherwise just draw the picture