What is the Del Operator in Vector Analysis and How Does It Work?

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The del operator, represented as ∇, is a mathematical tool in vector analysis defined in three-dimensional Cartesian coordinates, facilitating the calculation of gradient, curl, and divergence in vector fields. Its structure, comprising partial derivatives with respect to x, y, and z, is not arbitrary but serves to simplify mathematical notation and enhance comprehension of vector operations. While some may seek a deeper physical interpretation, the del operator is fundamentally a convention that streamlines complex equations. Understanding it as an operator that modifies functions according to specific rules can clarify its utility. The del operator's effectiveness lies in its design for convenience in mathematical applications.
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hello every one,
i am working on vector analysis and i have come across this definition of del operator.i don't understand where does it come from but it works great to determine rotation curl gradient or other stuff of a vector field.can anyone tell me how we are getting this magical operator is there a proof about this? in 2-D i ve found great deal of explanation about vectors but in 3-D it is really complicated.
i am looking forward to seeing your helps.
 
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The "del" operator is just defined in 3 dimensional, cartesian coordinates as \nabla=\bold{i}\frac{\partial}{\partial x}+\bold{j}\frac{\partial}{\partial y}+\bold{k}\frac{\partial}{\partial z}

I don't really understand what proof you are looking for; could you expand on your question?
 
i just want to know is it something special that this three partial derivatives working great to reveal these gradiant curl ..etc .or is it some thing good looking thing that appear in these equations as we try to determine curl, rotation.. so on?
 
In my opinion, you are probably asking what does del mean physically. It can't possibly appear from thin air, and all the mathematical results follow from it. I suggest this would help you:

http://en.wikipedia.org/wiki/Del

[PLAIN said:
http://en.wikipedia.org/wiki/Del][/PLAIN]
Del is a mathematical tool serving primarily as a convention for mathematical notation; it makes many equations easier to comprehend, write, and remember.

The above should clear your confusion up a little. It's simply a mathematical convention which has a lot of mathematical implications.
 
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thank u defennnder
it made great sense.
 
Operator is a function that can modify another function according to some rule, anything you want. A derivative is an operator because it changes a function to a different one according to a certain rule.

Del is "magical" because it was structured like that for our convenience. You use it with intuition whenever you like.
 
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There are probably loads of proofs of this online, but I do not want to cheat. Here is my attempt: Convexity says that $$f(\lambda a + (1-\lambda)b) \leq \lambda f(a) + (1-\lambda) f(b)$$ $$f(b + \lambda(a-b)) \leq f(b) + \lambda (f(a) - f(b))$$ We know from the intermediate value theorem that there exists a ##c \in (b,a)## such that $$\frac{f(a) - f(b)}{a-b} = f'(c).$$ Hence $$f(b + \lambda(a-b)) \leq f(b) + \lambda (a - b) f'(c))$$ $$\frac{f(b + \lambda(a-b)) - f(b)}{\lambda(a-b)}...

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