Vector Trigonometry

Trivium

  1. Given two points in two- or three-dimensional space:
    1. Calculate the distance between them and their midpoint.
    2. Determine a parameterization of the line that contains those points.
  2. Given two vectors in two- or three-dimensional space:
    1. Calculate and sketch any linear combination of them.
    2. Calculate the measure of the angle formed between them.
    3. Calculate the vector that results from projecting one onto the other.
    4. Calculate a vector that is orthogonal to both of them.
  3. Given three non-colinear points in space, determine an equation for the plane that contains those points.

Problems

  1. What is the shortest distance from the point \((-4,7)\) to the line \(3x-4y=10?\) In general, determine a formula for the shortest distance between a point \((p,q)\) and a line \(Ax+By=C\) in terms of \(p\) and \(q\) and \(A\) and \(B\) and \(C.\)
  2. [now in 3d] What is the shortest distance from the point \((TK)\) to the plane \(TK?\) In general, determine a formula for the shortest distance between a point \((p,q,r)\) and a plane \(Ax+By+Cz=D\) in terms of \(p\) and \(q\) and \(r\) and \(A\) and \(B\) and \(C\) and \(D.\)
  3. Given a line in three dimensional space and a point not on that line, compute the distance from the point to that line.
  4. Given two non-intersecting lines in space compute the closest distance between them.
  5. Given a plane in space and a line not parallel to that plane, determine the point at which the line intersects that plane.
  6. Given two non-parallel planes in space, determine a parameterization of the line along which they intersect.
  7. Suppose you’re swimming in a river with a current. What direction do you swim in to get across? [same but with a plane working against wind]
  8. Mr goat, but he can fly.
  9. 3d analog of the pipe problem from /synthetic
  10. Any two diagonals of a cube intersect in the center of the cube. What is the acute angle at which two diagonals of a cube intersect?
  11. TK Scalar triple product is volume of parallelepiped.