Is the Dot Product Distributive Property Just Too Simple?

AI Thread Summary
The discussion revolves around understanding the distributive property of the dot product in vector mathematics, particularly in a pre-calculus context. Participants express confusion over the simplicity of the property and seek clarification on the definitions and calculations involved. The standard definition of the dot product is provided as the sum of the products of corresponding components of two vectors. There is also mention of conflicting textbook definitions that complicate the understanding of the dot product. Overall, the thread highlights the need for clearer explanations and examples to grasp the concept effectively.
katrina007
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Need help with this problem. I need to show that one side equals the other. I this is distributive property but isn't that just too plain simple? I mean I am in pre-cal class and therefore this question can't be easy as it seems... ::biggrin:

anyways, if anyone knows about vector plez help me with this.

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Realize that the plus-symbol on the left applies to adding vectors,
whereas the plus-symbol on the right applies to adding scalars.

What is your working definition of the dot-product?
ab cos(angle between)? or ax*bx+ay*by+az*bz? or something else?
 
Hi,

Thanks for quick reply.
the teacher provide the following definition for the dot product:

The dot product of U = (U1, U2) and V = (V1, V2) is
U * V = U1V1 + U2V2
 
So, state the forms of each vector involved in terms of their components, then perform the scalar multiplications longhand. The definitions should drop right out.
 
i have a textbook that states; teh dot product of x1,x2 and y1,y2 is x1y1 - x2y1 -x1y2 + 4x2y2

how can that be? the it states the dot product of x1,x2 and x1,x2 is (x1-x2)^2 +3Xx^2 ? please help
 
I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
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