Help with Vector Components: Finding Magnitude and Direction

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The discussion focuses on calculating the magnitude and direction of vector components for a treasure hunt problem. Participants seek clarification on how to find angles and use trigonometric functions like sine, cosine, and tangent to determine vector components. Specific components for vectors A and B are provided, with A having a vertical component and B a horizontal one. The conversation emphasizes the importance of understanding the direction of vectors and how to apply the unit circle for angles, particularly for vector C. Ultimately, the total displacement vector D is calculated to be 4.66 m at an angle of 20.5 degrees.
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What are the magnitude and direction of the total displacement for the treasure hunt illustrated in Figure 3-9? Assume each pace is .750 m in length.

Question found in Physics 4th edition James S. Walker.

My question is when finding the components of vector C how do you find the angles and use the cos and sin? Or do you use tan? I honesty was lost because there was no example in the book that covered this particular material. There is no angle that was given or anything like that how can I find the components of C? And also when finding the angle for Vector D i had some troubles such as which numbers do I use?

Components of A = Ax = 0 Ay = 3.75

Components of B = Bx = 2.25 By = 0

Please guide me through this I am honesty lost in what formulas do I use and where is the angles? D=

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For the direction of C, what does southeast correspond to on a unit circle? (You can take the reference angle here...)

Then, what functions relate a distance and an angle to its components/projections?

After you find the angle for C and take the vector sum to get D, you can find the angle of D by relating its components. What trig function relates the x and y components of a triangle?
 
45 degrees so Cx = 2.12 Cy = -2.12

D = 4.66 m angle 20.5

pyth therom
 
You also need to take into account what direction the vector points. C is points to the right and down, so what should the signs of the components of C be?
 
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