I Where is this term coming from?

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The discussion revolves around the origin of an extra term in a mathematical expression, specifically related to the product rule in vector calculus. Participants clarify that the term likely arises from the x-direction component, denoted as x i-hat, while y and z components are ignored. One user expresses gratitude for the insight that helped them understand the reasoning behind the inclusion of the extra x. The conversation also touches on the need for proper mathematical notation, suggesting the use of LaTeX for clarity. Overall, the participants collaboratively work through the confusion surrounding the formula's components.
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I am back again to ask for your mathematical help.
I got the same result apart from that extra x in the second term? I have boiled it down to that it must have come from maybe the x hat j hat and z hat part of the product rule? Any help would be grateful thank you!
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It comes from numerator of the formula above, x i-hat.
 
@bigmike94 can you write down what ##A_x## is?
 
anuttarasammyak said:
It comes from numerator of the formula above, x i-hat.
Yeah I had a guess what assumed that was it but why is it included and not y or z aswell? Maybe I am missing an i hat which will get rid of the j and z hat cos of the dot product?
 
PeroK said:
@bigmike94 can you write down what ##A_x## is?
I’m not sure how to type maths in here but I think you have just helped me crack it, because it’s in the x direction only we ignore y hat and z hat, then In the product rule you’re left with the extra x.

I’m not sure if that makes sense to you? But yeah I think I get it now thank you
 
bigmike94 said:
I’m not sure how to type maths in here but I think you have just helped me crack it, because it’s in the x direction only we ignore y hat and z hat, then In the product rule you’re left with the extra x.

I’m not sure if that makes sense to you? But yeah I think I get it now thank you
By definition $$\vec A = A_x \hat i + A_y \hat j + A_z \hat k$$This can also be expressed as:$$A_x = \vec A \cdot \hat i$$

You need to learn some LaTex:

https://www.physicsforums.com/help/latexhelp/
 
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