Calculate the angle between:   a  =  (10, 5)T   and   b  =  (8, 12)T

A good answer might be:

The lengths are: | a |   =  125,   | b |   =  208.   The dot product is:

(10, 5)T/125 · (8, 12)T/208   =   (10*8 + 5*12) / (125 208)
=   140 / (125 208)   =   140/(125*208)
=   140/26000   =   0.86824

so the angle is:   arc cos ( 0.86824 )  =  29.745°

End of the Chapter

This chapter had quite a bit of numerical computation in it. Be careful that you did not loose sight of the important points. You may wish to go through this list to see what the important points were:

Click here     Click Here to go back to the Table of Contents

You have reached the end of the chapter.