Turn on thread page Beta
    • Thread Starter
    Offline

    6
    ReputationRep:
    Hi there, I'm looking for the answers for p3 may 2005.
    If no one has them could someone help me with:
    http://img233.echo.cx/img233/603/picture72vt.png

    Now there seems to be a typo, let's say that vector equation of line l is is:
    r=5i+11k....

    This is what I thought:
    (2i + j + 5k).(xi + yk + zk)=0
    2x + y + 5z = 0

    Maybe I should find the cartesian equation?
    Offline

    0
    ReputationRep:
    if its edexcel u r lookin for, iv got it..pm me ur email addy n i'll mail it

    Edit: oops i misread that
    iv got the jan'05 one!

    :rolleyes:
    • Thread Starter
    Offline

    6
    ReputationRep:
    oh , would you like to attempt it
    Offline

    10
    ReputationRep:
    (I guess you're talking about part b.)

    Since P lies on l, then it has position vector (2t, 5+t, 11+5t) relative to O, and since OP is perpendicular to l:
    OP . direction of l = 0
    (2t, 5+t, 11+5t) . (2, 1, 5) = 0
    4t + (5+t) + 5(11+5t) = 0
    t = -2

    So:
    OP = (-4, 3, 11)
    Offline

    0
    ReputationRep:
    there u go, someones done it already
 
 
 
Turn on thread page Beta
Updated: June 25, 2005
The home of Results and Clearing

1,257

people online now

1,567,000

students helped last year

University open days

  1. Bournemouth University
    Clearing Open Day Undergraduate
    Fri, 17 Aug '18
  2. University of Bolton
    Undergraduate Open Day Undergraduate
    Fri, 17 Aug '18
  3. Bishop Grosseteste University
    All Courses Undergraduate
    Fri, 17 Aug '18
Poll
Will you be tempted to trade up and get out of your firm offer on results day?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.