Is the Limit as x Approaches 2 of ((1/x)-(1/2))/(x-2) Zero?

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Homework Statement


lim
x\rightarrow2 ((1/x)-(1/2))/(x-2)


Homework Equations





The Attempt at a Solution


Limit x-> for all of them, too tedious to keep rewriting it
=((2/2x)-(x-2x))/(x-2)
=((2-x)/(2x))/(x-2)
=((2-x)/(2x)) * (1/(x-2))
=(2-x)/(2x^2-4x)
sub 2 in = 0/0 = 0

therefore when x approaches 2, y approaches 0?

=
 
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Never say 0/0=0. Never, until you have actually shown it. You have (2-x)/((2x)*(x-2)). (2-x)/(x-2)=-(x-2)/(x-2)=(-1). Now what's the limit?
 


Dick said:
Never say 0/0=0. Never, until you have actually shown it. You have (2-x)/((2x)*(x-2)). (2-x)/(x-2)=-(x-2)/(x-2)=(-1). Now what's the limit?


How did you go from (2-x)/((2x)*(x-2)) to (2-x)/(x-2)?
 


I didn't. I just separated (2-x)/((2x)*(x-2)) into [1/(2x)] * [(2-x)/(x-2)] and made the observation that the second factor is -1.
 


Dick said:
I didn't. I just separated (2-x)/((2x)*(x-2)) into [1/(2x)] * [(2-x)/(x-2)] and made the observation that the second factor is -1.

So then it is 0?

Btw, does the derivative of x/(2x-1) = 0?
 


TayTayDatDude said:
So then it is 0?

Btw, does the derivative of x/(2x-1) = 0?

Is what 0? No, the derivative of x/(2x-1) is not zero. Unless x=0.
 
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