A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing


  • one year ago

Question: a) Let P and Q be two points in space, and X the midpoint of the line segment PQ. Let O be an arbitrary fixed point; show that as vectors, OX = 1/2 (OP + OQ) . b) With the notation of part (a), assume that X divides the line segment PQ in the ratio r : s, where r + s = 1. Derive an expression for OX in terms of OP and OQ. Answer: a) OX = OP + PX = OP + 1/2(PQ) = OP + 1/2(OQ−OP)= 1/2(OP + OQ) b) OX = sOP + rOQ; replace 1/2 by r in above; use 1 − r = s. My Question: In the answer to part b, what does "replace 1/2 by r in above; use 1 − r = s" mean? How does it help?

  • This Question is Closed

    Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

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...


  • 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.