Question

http://screensnapr.com/v/ApaLmT.png
My teachers notes on how to do it (I still don't understand how to do it)
64] FT
Write each vector in component form by multiplying the numbers by the sines and cosines. Then you can add the first components and second components to get the sum of the vectors. To get the angle, just use the fact that the tangent is the y over the x. This problem could be worked out with triangle sketches and using the laws of signs and cosines. Using the vectors shows how powerful this technique is because it takes just a couple of minutes and about 3 less pages of work.

Answer 1

\[70\cos(-30^{o})i+70\sin30^{o}j\]

Answer 2

That's the first one.

Answer 3

\[40 \cos 45^{o}i+40\sin45^{o}j\]

Answer 4

So just do that for every single one that correlate together? 40 45 etc

Answer 5

That's the second one.

Answer 6

and 60 135 :0

Answer 7

\[60\cos 135^{o}i+60\sin135^{o}j\]

Answer 8

That's the third one.

Answer 9

Now add those and then convert back into the magnitude, angle form

Answer 10

Sorry if I fall asleep on you, just took some nyquil for my 101 fever! ;0

Answer 11

Umm the example of how to add them etc is a little messed up :S

Answer 12

As in http://screensnapr.com/v/y04Ovo.png

Answer 13

\[70\cos(-30)i+70sinj(-30)j=70(\frac{\sqrt{3}}{2})i+70(\frac{-1}{2})j\]

Answer 14

Unit circle?

Answer 15

\[40\cos45i+40\sin45j=40(\frac{\sqrt{2}}{2})i+40(\frac{\sqrt{2}}{2})j\]

Answer 16

yep.

Answer 17

\[60\cos135i+60\sin135j=60(-\frac{\sqrt{2}}{2})+60(\frac{\sqrt{2}}{2})j\]

Answer 18

Add them up. Probably want to convert to decimals.

Answer 19

And the magnitudes?

Answer 20

There will be only 1 magnitude. Did you add the vectors?