vectors: Three vectors each have a magnitude of 58 m and....

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soccerball3211

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Three vectors, a, b, and c, each have a magnitude of 58 m and lie in an xy plane. Their directions relative to the positive direction of the x axis are 29°, 195°, and 317°, respectively. What are (a) the magnitude and (b) the angle of the vector a+b+c, and (c) the magnitude and (d) the angle of a - b + c? What are (e) the magnitude and (f) the angle of a fourth vector d such that (a + b) - (c + d) = 0?

Can someone please check my answers to make sure I am doing this correctly?

Ok for a.) 46 m
b.) 325 degrees
c.) 150 m
d.) 1.53 degrees
e.) 71 m
f.) 133 degrees

Any help will be greatly appreciated! Thanks again
 
a. ok
b. ok
c. 149 m ... close enough
d. 1.37 degrees ... close enough
e. ok
f. 132 degrees ... close enough
 
325 degrees is not the correct answer. Could it possibly be that the question is using east as 0 degrees and not north?
 
I disagree ... 325 degrees is the correct direction for the sum a + b + c.

sum of the x-components ...
58[cos(29) + cos(195) + cos(317)] = approx 37.12

sum of the y-components ...
58[sin(29) + sin(195) + sin(317)] = approx -26.45

looking at the component sums, it's clear that the resultant lies in quad IV ...
\(\displaystyle \theta = -35.46^{\circ}\), which is coterminal with 324.53 degrees.
 
skeeter i came up with the same result as u did but i cant figure out why it wont register as the correct answer?

Thank you for your help!
 
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