A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the '''x''' and '''y''' axis being at right angles to each other and having a third, '''z''' axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
* '''The dot product''' (a scalar quantity)
:::: A • B = a1b1 + a2b2 + a3b3
* '''The cross product''' (a vector quantity)
:::: A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
* '''The scalar triple product''' (a scalar quantity)
:::: A • (B x C)
* '''The vector triple product''' (a vector quantity)
:::: A x (B x C)
;Task:
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
# Create a named function/subroutine/method to compute the dot product of two vectors.
# Create a function to compute the cross product of two vectors.
# Optionally create a function to compute the scalar triple product of three vectors.
# Optionally create a function to compute the vector triple product of three vectors.
# Compute and display: a • b
# Compute and display: a x b
# Compute and display: a • (b x c), the scalar triple product.
# Compute and display: a x (b x c), the vector triple product.
;References:
* A starting page on Wolfram MathWorld is {{Wolfram|Vector|Multiplication}}.
* Wikipedia [[wp:Dot product|dot product]].
* Wikipedia [[wp:Cross product|cross product]].
* Wikipedia [[wp:Triple product|triple product]].
;Related tasks:
* [[Dot product]]
* [[Quaternion type]]