What is the dot product of r   =   (6, 0)T with s   =   (0, 8)T?

A good answer might be:

(6, 0)T · (0, 8)T   =   6*0 + 0*8   =   0


Same Vectors, Rotated

 

The question was a particularly easy case. Here are the same two vectors rotated 45o:

r'   =   (  6cos(45),  6sin(45) )T
s'   =   ( -8sin(45),  8cos(45) )T

Don't worry too much about how I got the rotatated vectors. This topic will come up soon enough.


QUESTION 8:

Form the dot product of the two vectors:

r'   =   ( 2cos(45),  2sin(45) )
s'   =   ( -3sin(45),  3cos(45) )

(Yes, I know, this looks an awful lot like trigonometry. But it isn't. Just do it.)