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

modphysnoob

please look at my drawing @phi @KingGeorge

  • one year ago
  • one year ago

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

    |dw:1360298829035:dw| find this vector

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

    your x axis coordinate is incorrect

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

    it should be (4,0)

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

    yes , thanks

    • one year ago
  5. rebeccaskell94
    Best Response
    You've already chosen the best response.
    Medals 0

    That is a beautiful triangle you have there.

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

    then use mid point formula your gonna get, (2,1) as coordinates of bisector n then your vector is , V= 2i +j

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

    modphys doesn't want the mid point. He want the vector that's perpendicular.

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

    well thats perpendicular bisector that means dividing equally that means mid point

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

    What I would do, is write the line in the form \(y=-x/2+2\). The slope of the intersecting line will be \[-\frac{1}{-\frac{1}{2}}=2.\] So you have a line that looks like \(y=2x\) as the line that intersects. Set them equal to each other to get \(2x=-x/2+2\implies 5x/2=2\implies x=1\).

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

    Plug that in again, \(x=1\implies y=2(1)=2\), so the point of intersection is \((1,2)\).

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

    Which in turn means the vector is \[\vec{i}+2\vec{j}\]

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

    I got same answer but here what my book did

    • one year ago
    1 Attachment
  13. modphysnoob
    Best Response
    You've already chosen the best response.
    Medals 0

    • one year ago
    1 Attachment
  14. KingGeorge
    Best Response
    You've already chosen the best response.
    Medals 1

    If \(x=.8\), then the vector is \[.8\vec{i}+1.4\vec{j}\] Taking the dot product of that with the vector \[4\vec{i}-2\vec{j},\] we get \[.8\cdot4-2\cdot1.4=0.4\neq0\]so that solution is wrong.

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

    |dw:1360299909016:dw| just check the magnitude of vector A : (4*2)/sqrt(4^2+2^2) = 8/sqrt(20) = 8/2sqrt(5) = 4/5 * sqrt(5) 0.8 and 1.6 has the same magnitude

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

    Just as in your book, we can say the direction vector B (from pt (0,2) to (4,0) is (4,-2) let vector A be perpendicular to B. A dot B = 0 (x,y) dot (4,-2) =0 we get 4x = 2y pick a nice number for x, like 1. then y =2 vector A = (1,2) is perpendicular to vector B make A unit length, by dividing by its length. |A|= sqrt(5) Au = (1,2)/sqrt(5) now to get the length to scale Au so it reaches the line between (0,2) and (4,0), we notice that the vector (4,0) projected onto Au has the correct length Au dot (4,0) = 4/sqrt(5) The vector we want is 4/sqrt(5) * (1,2)/sqrt(5) = 4/5 * (1,2) or (0.8, 1.6)

    • 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.