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   Vector Multiplication .
   Wikipedia   dot product. 
   Wikipedia   cross product. 
   Wikipedia   triple product.


Related tasks

   Dot product
   Quaternion type


To run:
Start up.
Make a vector from 3 and 4 and 5.
Make another vector from 4 and 3 and 5.
Make a third vector from -5 and -12 and -13.
Write "A vector: " then the vector on the console.
Write "Another vector: " then the other vector on the console.
Write "A third vector: " then the third vector on the console.
Write "" on the console.
Compute a dot product of the vector and the other vector.
Write "Dot product between the vector and the other vector: " then the dot product on the console.
Compute a cross product of the vector and the other vector.
Write "Cross product between the vector and the other vector: " then the cross product on the console.
Compute a scalar triple product of the vector and the other vector and the third vector.
Write "Scalar triple product between the vector and the other vector and the third vector: " then the scalar triple product on the console.
Compute a vector triple product of the vector and the other vector and the third vector.
Write "Vector triple product between the vector and the other vector and the third vector: " then the vector triple product on the console.
Wait for the escape key.
Shut down.
 
A vector has a first number, a second number, and a third number.
 
To make a vector from a first number and a second number and a third number:
Put the first into the vector's first.
Put the second into the vector's second.
Put the third into the vector's third.
 
To put a vector into another vector:
Put the vector's first into the other vector's first.
Put the vector's second into the other vector's second.
Put the vector's third into the other vector's third.
 
To convert a vector into a string:
Append "(" then the vector's first then ", " then the vector's second then ", " then the vector's third then ")" to the string.
 
A dot product is a number.
 
To compute a dot product of a vector and another vector:
Put the vector's first times the other vector's first into a first number.
Put the vector's second times the other vector's second into a second number.
Put the vector's third times the other vector's third into a third number.
Put the first plus the second plus the third into the dot product.
 
A cross product is a vector.
 
To compute a cross product of a vector and another vector:
Put the vector's second times the other vector's third into a first number.
Put the vector's third times the other vector's second into a second number.
Put the vector's third times the other vector's first into a third number.
Put the vector's first times the other vector's third into a fourth number.
Put the vector's first times the other vector's second into a fifth number.
Put the vector's second times the other vector's first into a sixth number.
Make a result vector from the first minus the second and the third minus the fourth and the fifth minus the sixth.
Put the result into the cross product.
 
A scalar triple product is a number.
 
To compute a scalar triple product of a vector and another vector and a third vector:
Compute a cross product of the other vector and the third vector.
Compute a dot product of the vector and the cross product.
Put the dot product into the scalar triple product.
 
A vector triple product is a vector.
 
To compute a vector triple product of a vector and another vector and a third vector:
Compute a cross product of the other vector and the third vector.
Compute another cross product of the vector and the cross product.
Put the other cross product into the vector triple product.