Date of the lesson: 31 Oct 2011
In order to solve exercises involving vectors, trigonometric identities come very handy. For instance:
And don’t forget the prosthaphaeresis formulae!
One important relationship is the Law of Sines:
Summing vector is easy as long as you project each vector along the coordinate axes. Five steps north, two steps east, three steps south…
How to fly a plane from Bologna to Prague:
- Calculate and , where: ,
- The resultant vector has length . The angle between and is . Knowing that the angle , find the length of and .
- Calculate the angle between ,
- For the die-hard: calculate the area of the triangle defined by vertices A(-1,2,3) B(2,-1,1) C(1,3,2)