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

Calcmathlete Group Title

Given \(\vec{g} = -3\vec{i} + 6\vec{j} - 12\vec{k}\) and \(\vec{h} = 5\vec{i} - 10\vec{j} + 20\vec{k}\), how could I prove that \(\vec{g}\) and \(\vec{h}\) are parallel? Please explain the reasoning.

  • one year ago
  • one year ago

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

    take their vector product, or prove they are multiple of each other

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

    Well does a vector product of 0 allow me to conclude that they are parallel?

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

    yes

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

    g x h=|g||h|sin(theta) where theta is angle between them. It will be = 0 only if angle is 0º or 180º

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

    Ok, just clarifying, is it because using the formal definition of the magnitude of a vector product, if \(\theta\) = 0º or 180º, it would cause the entire thing to become 0, and therefore parallel since an angle of 0º or 180º would be the same line or parallel?

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

    yes

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

    Oh, never mind, thank you!

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

    yw

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

    more easy: -5/3(-3i+6j-12h)=5i-10j+20k

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

    so -5/3g=h

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

    Ok. that is the reason the book gave me, so I'm curious as to why that works...I don't see where -5/3 comes from.

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

    to make -3 equal to 5

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

    Oh. so you're multiplying \(\vec{g}\) by -5/3 to make it equal \(\vec{h}\)?

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

    yes

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

    ok, once again, thank you :)

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

    yw, :)

    • 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.