Subtracting Vectors: How to Find Magnitude of A-B

AI Thread Summary
To find the magnitude of the vector difference (A-B), convert the vectors A and B into their rectangular components using trigonometric functions based on their magnitudes and angles. After calculating the components, subtract the corresponding components of vector B from vector A. Finally, convert the resulting vector back into polar form to find its magnitude. Understanding the conversion between rectangular and polar coordinates is crucial for solving this problem effectively. This approach will clarify the process of vector subtraction and help in obtaining the correct magnitude.
nrdiamon
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This is the problem that I was given:

Given two vectors A and B, with magnitudes |A| = 45.7 and |B|=38.2 and directions (from the x-axis) θA=64° and θB=145°, find the magnitude of (A-B)

I know that this somehow involves triangles and trigonometry, but I am really confused as to how I do this. Please help!
 
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nrdiamon said:
This is the problem that I was given:

Given two vectors A and B, with magnitudes |A| = 45.7 and |B|=38.2 and directions (from the x-axis) θA=64° and θB=145°, find the magnitude of (A-B)

I know that this somehow involves triangles and trigonometry, but I am really confused as to how I do this. Please help!

Welcome to the PF. To add/subtract vectors, you will use rectangular coordinates and rectangular components, and then convert back into polar form if needed for the final answer.

Does that make sense? If not, go to wikipedia.org, and search on vector rectangular polar conversion. Actually a better match at wiki is vector polar coordinate system...
 

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