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

haterofmath Group Title

√((18)/(36))=(√(2))/(2)

  • one year ago
  • one year ago

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

    \[\frac{ \sqrt{18} }{ \sqrt{36} }=\frac{ \sqrt{2} }{ 2 }\]

    • one year ago
  2. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yes. you can see it is true by factoring each number into its prime factors 18 is 2*9 = 2*3*3 36 is 2*18= 2*2*9= 2*2*3*3 when these are under a square root \[ \frac{\sqrt{2\cdot 3\cdot 3}}{\sqrt{2\cdot 2\cdot 3 \cdot 3} }\] you can "pull out" pairs. in the top, 3*3 out of the square root becomes 3 in the bottom both 2 and 3 come out \[ \frac{3 \sqrt{2}}{2\cdot 3} \] we can divide top and bottom by 3 to simplify to \[ \frac{\sqrt{2}}{2} \]

    • one year ago
  3. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    of course, if you know 6*6=36 you can just replace the bottom sqrt(36) with 6 right away.

    • one year ago
  4. haterofmath Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    so the question ask to simplify

    • one year ago
  5. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    sqrt(2)/2 is as simple as it gets. you could write it as 1/sqrt(2) but people do not sqrt's in the denominator.

    • one year ago
  6. haterofmath Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    ok. so i have another problem...it says to multiply and simplify \[(3\sqrt{10}-2\sqrt{2})^2=98-24\sqrt{5}\]

    • one year ago
  7. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    it looks like they gave you the answer. But to show how to do it, use FOIL on ( 3 sqrt(10) - 2 sqrt(2) )* ( 3 sqrt(10) - 2 sqrt(2) )

    • one year ago
  8. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    here is an example of how to do this http://www.khanacademy.org/math/algebra/polynomials/v/multiplying-binomials-with-radicals

    • one year ago
  9. haterofmath Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    so it will just be \[(3\sqrt{10}-2\sqrt{2})(3\sqrt{10}-2\sqrt{2})=98-24\sqrt{5}\]

    • one year ago
  10. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yes, but I think they want you to do the multiplication and get the answer they show you.

    • one year ago
  11. haterofmath Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    how would you do that?

    • one year ago
  12. phi Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    This video http://www.khanacademy.org/math/algebra/polynomials/v/multiplying-binomials and the other one posted go into the details.

    • one year 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.