How Do You Prove the Limit of a Vector Function?

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physicsidiot1
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proof for a vector limit??

Homework Statement


Show that the lim(t-->a)r(t)=b. if and only if for every [tex]\epsilon[/tex]>0 there is a number [tex]\delta[/tex]>0 such that if 0<|t-a|<[tex]\delta[/tex] then |r(t)-b|<[tex]\epsilon[/tex]

This is asking to prove the limit of a vector function.
It seems to me that within the question, it is already answered...I don't know how else to show that limit exists other than with what is said above.


Homework Equations


usual epsilon delta stuff


The Attempt at a Solution


I really don't know
 
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physicsidiot1 said:

Homework Statement


Show that the lim(t-->a)r(t)=b. if and only if for every [tex]\epsilon[/tex]>0 there is a number [tex]\delta[/tex]>0 such that if 0<|t-a|<[tex]\delta[/tex] then |r(t)-b|<[tex]\epsilon[/tex]

This is asking to prove the limit of a vector function.
It seems to me that within the question, it is already answered...I don't know how else to show that limit exists other than with what is said above.

I'm guessing here, but perhaps the above is not what you were given for definition of the limit of a vector function. Maybe your definition was given in terms of limits of components, something like this:

Define R(t) = <x(t),y(t),z(t)>. If

limt→ax(t) = b1 and
limt→ay(t) = b2 and
limt→az(t) = b3

then we say limt→aR(t) = b =<b1,b2,b3>

If that is the case, you have something to prove.