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Precise Definition of a limit

  • Thread starter step1536
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  • #1
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Homework Statement





Homework Equations





The Attempt at a Solution



How close to 2 do we have to take x so that 5x+3 is within a distance of 0.075 from 13.
I am confuse on how to evaluate this problem.
 

Answers and Replies

  • #2
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You should state your question more clearly.

A distance of 0.075 from 13 can be 13 + 0.075 or 13 - 0.075. Can you find an x such that 5x+3 evaluates to one of those two points?
 
  • #3
HallsofIvy
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5x+3 will be within distance 0.075 from 13 (above or below) as long as 5x+ 3 is between 13- 0.75 and 13+ 0.75 or [itex]12.25\le 5x+ 3\le 13.75[/itex]. Solve that inequality for x. How close is that to 2?
 
  • #4
19
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I understand that part but how do you work the problem out?
 
  • #5
19
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so x=1.85,2.15; then I would then subtract 2-1.85 and 2-2.15. my answer would be .15
 

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