Scalar multiplication of two equal vectors

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Homework Help Overview

The discussion revolves around the scalar multiplication of vectors, specifically addressing the confusion regarding the product of a vector with itself and its relation to unit vectors.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the meaning of scalar multiplication of a vector by itself, questioning the assertion that it equals 1. They discuss the implications of unit vectors and the context in which the professor made the statement.

Discussion Status

There is an ongoing exploration of the professor's statement, with participants questioning its validity and seeking clarification on the context. Some suggest that the professor may have been referring to unit vectors, while others express confusion about the definition and properties of vectors in this context.

Contextual Notes

Participants note the potential misunderstanding regarding the definition of unit vectors and the conditions under which scalar multiplication yields specific results. There is an emphasis on the need for clarity regarding the professor's remarks and the assumptions being made.

transgalactic
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i have vector "a"

why a*a=1??

it make no sense

the formula says |a|*|a|*cos0=a^2 (not 1)
 
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Hi transgalactic! :smile:
transgalactic said:
i have vector "a"

why a*a=1??

it make no sense

the formula says |a|*|a|*cos0=a^2 (not 1)

But cos0 = 1,

so that means |a|*|a| = a^2, which is correct. :smile:

Where does your a*a=1 come from? :confused:
 
from my professor in physics :(
 
transgalactic said:
from my professor in physics :(

Well, what was the context, then?

What else was he/she talking about at the time?

Unit vectors? Basis vectors? General vectors? Hilbert spaces?
 
he just stated that if we multiply scalarly a vector(in general) by itself
we will get 1
 
transgalactic said:
he just stated that if we multiply scalarly a vector(in general) by itself
we will get 1

hmm … that's obviously rubbish …

i suppose he must have been thinking of applying that to some specific equation that he didn't actaully mention. :confused:
 
ill try to confront him with this problem
 
Are you sure he didn't say a unit vector?
 
unit vector represents a single unit with the direction of a certain axes
i think you are correct
why their multiplication equals 1?

nobody said their length is 1
only that its the smallest unit of length with a direction

??
 

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