Shedding some light on the dot product

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The dot product of two vectors A and B is commutative, meaning A . B equals B . A. When finding the components of vector V in the direction of vector W, the order of the vectors in the dot product does not matter. However, to determine the component of V along W, one must multiply V by the unit vector of W, not just use the dot product. The magnitude of this projection is calculated as V . W divided by the magnitude of W. Understanding these concepts is crucial for accurately analyzing vector components in geometry.
cytochrome
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The dot product A . B is the magnitude of vector A times the projection of B onto A.

B . A is the magnitude of vector B times the projection of A onto B.

Correct?

A . B = B . A and this makes sense. But, say you're trying to find the components of a vector V in the direction of a vector W. Would it matter whether or not you wrote V . W or W . V?

EDIT: Also, does anyone know what it means (geometrically speaking) to find the components of a vector in the direction of another vector? I can give an example from a book if needed.
 
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To the first question, no it wouldn't matter. The dot product is commutative so ##\vec{V} \cdot \vec{W} = \vec{W} \cdot \vec{V}## for any vectors V and W.

To the edit, imagine you have your vector lying in the plane. Now imagine it is the hypotenuse of a right triangle where one of the sides of the triangle is parallel to the x-axis and the other side is parallel to the y-axis. The component of the main vector (which remember is represented as the hypotenuse) in the x direction is the length of the side of the triangle parallel to the x-axis, and the same for the y direction.
 
cytochrome said:
The dot product A . B is the magnitude of
A . B = B . A and this makes sense. But, say you're trying to find the components of a vector V in the direction of a vector W. Would it matter whether or not you wrote V . W or W . V?

It does not matter which way you write. But none of them will give you the component of V along the direction of W.
You need to multiply V by the unit vector along W.
So the magnitude of the projection is given by V.W/W
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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