anonymous one year ago Find the specified vector or scalar. Show your work. u = -4i + 1j and v = 4i + 1j; Find .||u+v||

1. anonymous

@freckles

2. Kainui

Find what?

3. anonymous

idk let me ask my teacher thats how the question was given to me

4. anonymous

||u+v||

5. anonymous

@freckles

6. freckles

(ai+bj)+(ci+dj) =(a+c)i+(b+d)j then to find the magnitude of that sum you do $\sqrt{(a+c)^2+(b+d)^2}$

7. anonymous

ok this is my first time doing this soo

8. anonymous

i dont know what to do ?

9. anonymous

@mathmath333

10. anonymous

@freckles

11. anonymous

@skullpatrol

12. freckles

13. freckles

-4+4=?

14. freckles

15. freckles

$u+v=(-4+4)i+(1+1)j$

16. anonymous

1+1= 2 and -4+40

17. anonymous

sorry -4+4=0

18. freckles

ok so you saying u+v=0i+2j or just u+v=2j

19. freckles

now how far is that from the origin ?

20. freckles

|dw:1438892786063:dw|

21. anonymous

like three away maybe more of two maybe

22. freckles

|dw:1438892855065:dw|

23. anonymous

zaro

24. freckles

1+1 =2

25. anonymous

opps i read that wrong my apologizes

26. freckles

you could have also used the formula above $\sqrt{0^2+2^2}=\sqrt{0+4}=\sqrt{4}=2$

27. freckles

but yeah 2j is just 2 units away from the origin

28. freckles

nj where n is a real number is just |n| units away from the origin

29. freckles

magnitude is just concerned how far something is from the origin

30. anonymous

ohh ok well thnx then thnx alot

31. freckles

np