Find C vector, with two known magnitudes

AI Thread Summary
The discussion revolves around solving a physics problem involving vector C with two known magnitudes using the law of cosines. The user expresses confusion and seeks clarification on the correct method to apply, specifically regarding the calculation involving the square root of the sum of squares and the cosine of the angle. Another participant confirms that the approach is accurate and offers encouragement. The conversation emphasizes the importance of understanding vector addition and the law of cosines in solving such problems. Overall, the thread highlights the collaborative effort to clarify a challenging physics concept.
Casodd
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Homework Statement


https://i.imgur.com/UtLzb34.png

Homework Equations


the law of cosinus

The Attempt at a Solution


I have not been available to scan my work, but I'm kinda stuck at the beginning. And our teacher have not show us this kind of physics yet.
Thanks.
 
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Welcome to PF, what method have you already tried? I'm assuming you are using the tail-to-tip method since the law of cosines relevant. What exactly are you having trouble with?

Edit: I would appreciate even just a photo of your work (make sure its neat and legible).
 
So all I have to do is take the square root of ( |A|^2+ |B|^2cos79 ) ?
and then do tan delta to find the degree? (Which is not the question) ?
picture:
Q87BV0L.png


Thanks for answering.
 

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Casodd said:
So all I have to do is take the square root of ( |A|^2+ |B|^2cos79 ) ?
and then do tan delta to find the degree? (Which is not the question) ?
picture:
View attachment 218369

Thanks for answering.
Yes, this looks accurate. That's how I did it. Good job!
 
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