Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

ganeshie8 Group Title

i am getting two solutions for this problem. but only one is satisfying the equation. could someone pls explain whats going on... http://assets.openstudy.com/updates/attachments/50064e0ae4b0624180677e0a-emily9102-1342590484915-mathproblem5.jpg

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. f1r1e1s1h1 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    square it and try?

    • 2 years ago
  2. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1342591850277:dw|

    • 2 years ago
  3. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    x =1 is not satisfying the equation :( not sure why

    • 2 years ago
  4. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    hmm

    • 2 years ago
  5. f1r1e1s1h1 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    man u have squared it so ofcourse one will not match?

    • 2 years ago
  6. higgs Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    when you square something, you will always get two solutions, and not all of them will be right. substitute the answers back into the original equation to check. in this case, 1 is not the solution as -1 is not equal to 1

    • 2 years ago
  7. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    im li'l lost.... could u elaborate pls.. ?

    • 2 years ago
  8. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    i see we are squaring... and losing sign sensitivity is it

    • 2 years ago
  9. mukushla Group Title
    Best Response
    You've already chosen the best response.
    Medals 2

    u must consider restrictions in every step note that when u have \( x-3=2 \sqrt{x} \) then \( x-3 \ge0 \)

    • 2 years ago
  10. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    ah that makes sense. thanks mukushla straight to the point. :)

    • 2 years ago
  11. mukushla Group Title
    Best Response
    You've already chosen the best response.
    Medals 2

    welcome my friend

    • 2 years ago
  12. higgs Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    I suppose this also applies to irrational equations like this? \[\sqrt{x-1}+\sqrt{x+4}=\sqrt{3x+10}\] I got \(x = 5\) and \(x = \frac{-13}{3} \) \(x = \frac{-13}{3} \) is rejected in this case as well because after substituting into the equation, it became undefined.

    • 2 years ago
  13. ganeshie8 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yeah now i understand thanks higgs :D here, from the first equation itself, we can apply the restriction x >=1. and hence rejected solutions < 1

    • 2 years ago
  14. No.name Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    The sollutions we get after solving , and which does not satisfy the origanal question are called extraneous sollutions. There occurred as we have squared , so there is a chance of getting a extraneous sollution.

    • 2 months ago
    • Attachments:

See more questions >>>

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.