# Math Help - vector problem

1. ## vector problem

Given the following vectors: = 3.9 + 3.1, = 3.3 + 3.1, and = 2.5 + 8.3
(a) Find the vector , in unit vector notation, such that + 2 - 2 + 2 = 0.
+

(b) Express your answer in part (a) in terms of magnitude and angle clockwise from the + x direction.
at °

webassign continues to call me wrong on this and ive asked everyone i know and they get the same thing. help?

2. oops didnt post the numbers.

its -9.4 i and 4.2 j

and the magnitude is 10.296

the angle i got was 204.075

3. $D = - 9.4i + 4.2j$, this what MathCad gives as the answer.

$\left\| D \right\| = 10.296\,\& \,\phi = \pi + \arctan \left( {\frac{{ - 9.4}}{{4.2}}} \right) = {\rm{2}}{\rm{.721}} \approx {\rm{155}}{\rm{.925}}^ \circ$

4. well isnt that the angle COUNTERclockwise from the +x axis?
it asks for clockwise, which is weird but my teacher is tricksy.

5. Well try that to see if it works. It may be a missprint.
Or try $-204.075^o$.

6. hmm good point i suppose it could be a missprint.
i only have one more submission though you only get three and i already used the first two on that answer ( i got frustrated and tried it twice).
maybe ill just email my teacher.