A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Find the domain of the function f(x)= x^2/(7x-1) and leave your answer in set notation.

  • This Question is Closed
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[f(x)=\frac{ x ^{2} }{ 7x-1 }\]

  2. perl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 3

    The domain is the set of all real number inputs that make sense. Does it make sense to divide by zero?

  3. imqwerty
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    R-{1/7}

  4. theEric
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I agree with @perl. The thing is, ALL functions have domains - that is a required for a function to be a function. Just, it's \(\it{assumed}\) a lot of the time. So, when no one tells you what it is, you have to assume that your \(x\) can be any value that gives you a result in the "range." That is the range part of the domain and range that are needed for the function. Normally, we make another assumption - the range is real numbers only (no \(\sqrt{-1}\), for sure). So, the result of the function needs a value! Some expressions are undefined, like \(\dfrac{\text{anything}}0\). So, if some value would make \(f(x)\) be \(\dfrac{\text{anything}}0\), then \(x\) is NOT that. In other problems, you might see something like \(g(x)=\sqrt x\). If \(x\) is negative, like \(\sqrt{-4}\), the result is not real, and we don't want it. There, we say \(x\) is NOT negative, so \(x>0\).

  5. 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

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.