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Stuck Again : -->

  • Thread starter Hardikph
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  • #1
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I was doin' some coursera quiz. It asked this question :
Let ƒ(x) = (x2 - x - 42) / x-7
find as x → 7.
Now I approach x from both sides and it get me 2 different answer.
So which one is correct:
13 or 14?
 

Answers and Replies

  • #2
haruspex
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View attachment 102575 I was doin' some coursera quiz. It asked this question :
Let ƒ(x) = (x2 - x - 42) / x-7
find as x → 7.
Now I approach x from both sides and it get me 2 different answer.
So which one is correct:
13 or 14?
Please post your working.
 
  • #3
SteamKing
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Also, please try to post your HW threads in the appropriate HW forum by topic.
 
  • #4
symbolipoint
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Note that simplifying f will give the LINE y=x+6, and the FUNCTION is undefined for x=7. The limit at x=7 is that missing point. You just need to set x=7 for y=x+6.
 
  • #5
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OK get It.
 
  • #6
Ray Vickson
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View attachment 102575 I was doin' some coursera quiz. It asked this question :
Let ƒ(x) = (x2 - x - 42) / x-7
find as x → 7.
Now I approach x from both sides and it get me 2 different answer.
So which one is correct:
13 or 14?
The function is not ##f(x) = \frac{x^2-x-42}{x} -7##, as you wrote.
 
  • #7
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The function is not ##f(x) = \frac{x^2-x-42}{x} -7##, as you wrote.
Yes it must be like ƒ(x) = (x2 - x - 42) / (x-7).
 

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