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isabellaxochitl Group Title

what are the critical numbers of f(x)= 4x/(x^2 +1)?

  • one year ago
  • one year ago

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  1. dpaInc Group Title
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    did u already calculate the derivative?

    • one year ago
  2. dpaInc Group Title
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    what's f ' (x) = ??

    • one year ago
  3. Goten77 Group Title
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    |dw:1358921318013:dw|

    • one year ago
  4. isabellaxochitl Group Title
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    do i simplify it further or just set it to 0 now?

    • one year ago
  5. Goten77 Group Title
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    to simplify makes setting it = to 0 much easier

    • one year ago
  6. isabellaxochitl Group Title
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    ok i need help simplifying it…i don't think i am doing it right so far

    • one year ago
  7. Goten77 Group Title
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    k also the critical points are what makes the top part become 0 .. or what makes the bottom part not exist.. in this case all reals exist on the domain... so we just gotta worry bout setting the top = to 0

    • one year ago
  8. isabellaxochitl Group Title
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    so i just completely forget the bottom part?

    • one year ago
  9. Goten77 Group Title
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    |dw:1358921549240:dw|

    • one year ago
  10. Goten77 Group Title
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    i wouldnt say forget bout the bottom part... but usually in the 1st derivative test its worthless.. unless theres a square root or something that might make it non existiant

    • one year ago
  11. Goten77 Group Title
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    hmm let me think... i gotta make sure i didnt say soemthing wrong

    • one year ago
  12. isabellaxochitl Group Title
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    |dw:1358921732409:dw|

    • one year ago
  13. isabellaxochitl Group Title
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    wait wait that was wrong i got it its 1

    • one year ago
  14. Goten77 Group Title
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    k i also need to add that critical points are when the derivative = 0 on the bottom or top.. and when its undefined... but it must all be in the domain

    • one year ago
  15. Goten77 Group Title
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    We say that x=c is a critical point of the function f(x) if exists and if either of the following are true. f'(c)=0 or doesnt exist

    • one year ago
  16. Goten77 Group Title
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    |dw:1358922243760:dw|

    • one year ago
  17. Goten77 Group Title
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    but ultimately the 1 and -1 are the critical points... sorry i kinda am lost in calculus *been a while since i did it* but making the top = to 0 and finding where stuff doesnt exist is where critical points are.... srry if i say something wrong but this info should be correct

    • one year ago
  18. isabellaxochitl Group Title
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    thanks for the help!

    • one year ago
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