Cosine of a vector.

  • #1

Homework Statement


The cosine of a vector is equal to the opposite over its magnitude.

Homework Equations



The attempt at a solution[/b] the cosine is the ratio of the adjacent to the hypothenuse this is why i say it "came' is incorrect.
 

Answers and Replies

  • #2
haruspex
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What exactly was the original question?
 
  • #3
What exactly was the original question?
That is the ?,its a true or false
 
  • #4
NascentOxygen
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That is the ?,its a true or false
What statement is true or false?

Oh, I see. It's this statement that's being questioned:
The cosine of a vector is equal to the opposite over its magnitude.

Yes, it's an incorrect statement, as you pointed out.
 
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  • #6
NascentOxygen
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It's not the vector which has a cosine. It's only angles which have cosines.
 
  • #7
HallsofIvy
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Homework Statement


The cosine of a vector is equal to the opposite over its magnitude.
If this really is the statement, I would not say it was either "true" or "false". I would just say it is non-sense! The function "cosine" is not [g]defined[/b] for vectors, only for angles or numbers. Further, saying "the opposite" is non-sense. "Opposite" is an adjective not a noun and cannot take the article "the".

Homework Equations



The attempt at a solution
the cosine is the ratio of the adjacent to the hypothenuse this is why i say it "came' is incorrect.
 
  • #8
vela
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Just out of curiosity, what is
this is why i say it "came' is incorrect.
supposed to mean?
 
  • #9
NascentOxygen
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Just out of curiosity, what is
[ C A M ]
supposed to mean?

cosine = adjacent ÷ magnitude ?
 
  • #10
vela
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Wouldn't that be correct?
 
  • #11
NascentOxygen
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Wouldn't that be correct?
Clearly, OP is a little confused.
 
  • #12
cosine

Clearly, OP is a little confused.


The question was asking whether the statement ' cosine means the y component of a vector over its magnitude'.
Is this true or false?
 
  • #13
NascentOxygen
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The question was asking whether the statement ' cosine means the y component of a vector over its magnitude'.
Is this true or false?
Definitely false.
 

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