Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

cleverlikeme

  • 3 years ago

I need help with the steps involved to solve the following equation. lim x→−24 (square root(x^2 + 49) − 25)/x + 24 obviously when i plug it in its 0/0 but I'm unsure of the method to solve at this point. if there wasnt a square root i could try factoring and reducing, but with the root in there i don't know how to proceed. thanks!

  • This Question is Open
  1. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Do you know l'hopital's rule?

  2. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    That should really be enough, in my opinion.

  3. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Or the definition of derivative.

  4. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Assume \(h =x + 24 \), then the limit is written as the following:\[\lim_{h\to 0} \left(\sqrt{x^2 + 49} - 25 \over h\right) \]

  5. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Hmm, the definition of derivative doesn't apply here. NVM

  6. cleverlikeme
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    surprisingly enough, we havent covered derivatives yet. or that rule

  7. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Darn.

  8. cleverlikeme
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I haven't had math in years and I'm pretty lost in this class. what we have covered are the limit laws; sum, difference, constant multiple, product, quotient

  9. shubhamsrg
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 4

    You should rationalize the numerator. Must help.

  10. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yay, rationalizing helped me. Shubham, Y U NO REPLY TWO SECONDS LATER?

  11. shubhamsrg
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 4

    I may delete my comment if you ask for it! ;)

  12. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    No, you have your credit.

  13. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    :-P

  14. anonymous
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    try \[\frac{\sqrt{x^2+49}-25}{x-24}\times \frac{\sqrt{x^2-49}+25}{\sqrt{x^2-49}+25}\]

  15. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes, that's what I did there. Conjugation for the win.

  16. anonymous
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok that was wrong!!

  17. ParthKohli
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    No it wasn't?

  18. anonymous
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\frac{\sqrt{x^2+49}-25}{x+24}\times \frac{\sqrt{x^2+49}+25}{\sqrt{x^2+49}+25}\] is more like it

  19. cleverlikeme
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I tried that, which gets me \[\frac{ (x^2+49)-625 }{ (x+24) * (\sqrt{x^2+49} +25) }\] Or I think it does. And I'm not sure where to go from there.

  20. shubhamsrg
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 4

    -49+625 = -576 = -(24^2) Does it help ?

  21. cleverlikeme
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes! I'm so bad at factoring, I dont ever seem to see stuff like that

  22. shubhamsrg
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 4

    Glad to have helped! ^_^

  23. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy