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Simple Vector question.

  • Thread starter arianabedi
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  • #1
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Homework Statement


This is a "exam style" question for A-Level mathematics regarding vectors. The question is as followed:

Relative to a fixed origin O, the points A and B have position vectors 4i+3j-k and i+4j+4k respectively.

(a) Find the vector equation of the line l1 which passes through A and B.

The line l2 has equation r=22i+aj+4k+μ(bi-j+2k), where μ is scalar parameter and a and b are constants.
The lines l1 and l2 are perpendicular and intersect. Find:

(b) the values of a and b

(c) the position vector of the point of intersection of l1 and l2

Homework Equations


Vector equation of a strait line through two points C and D:

r=c+t(d-c)

if there is any other ones, I am unfortunately unaware of

The Attempt at a Solution



Sadly I've been given no knowledge of how to do this question since vectors is not a part of my course. Therefore there are no attempts made


4.Conclusion
This question is really getting into my head and any help would be greatly appreciated.

Regards,
-A
 
Last edited:

Answers and Replies

  • #2
33,271
4,980

Homework Statement


This is a "exam style" question for A-Level mathematics regarding vectors. The question is as followed:

Relative to a fixed origin O, the points A and B have position vectors 4i+3j-k and i+4j+4k respectively.

(a) Find the vector equation of the line l1 which passes through A and B.

The line l2 has equation r=22i+aj+4k+μ(bi-j+2k), where μ is scalar parameter and a and b are constants.
The lines l1 and l2 are perpendicular and intersect. Find:

(b) the values of a and b

(c) the position vector of the point of intersection of l1 and l2

Homework Equations


Vector equation of a strait line through two points C and D:

r=c+t(d-c)

if there is any other ones, I am unfortunately unaware of

The Attempt at a Solution



Sadly I've been given no knowledge of how to do this question since vectors is not a part of my course. Therefore there are no attempts made
Then why don't you wait until vectors are presented in your course, or when you take a course where vectors are presented?
4.Conclusion
This question is really getting into my head and any help would be greatly appreciated.

Regards,
-A
 
  • #3
38
0
Then why don't you wait until vectors are presented in your course, or when you take a course where vectors are presented?
Well the reason is that I've been told by my tutor that I will not be studying vectors.
 
  • #4
33,271
4,980
Then how do you expect to be able to solve problems that involve vectors?
 
  • #5
HallsofIvy
Science Advisor
Homework Helper
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For this problem, all you really need to know is that a point with position vector ai+ bj+ ck has coordinates (a, b, c).
 

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