-  . . .  floor.1
- By 
 convention, angles are measured counter-clockwise 
 from the reference axis, so technically  is negative; this makes no difference to its cosine.  
 Thus is negative; this makes no difference to its cosine.  
 Thus is initially positive and is initially positive and is initially negative. is initially negative..
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-  . . . 
negative.2
- Again the convention is 
 to treat counter-clockwise rotations as positive; 
 by inspection we can see that  must be clockwise, 
 so must be clockwise, 
 so .
As long as a consistent notation is used, 
 it doesn't matter if the direction shown is opposite to the 
 actual direction; the answer will always come out of any 
 correct calculation with the required minus sign. .
As long as a consistent notation is used, 
 it doesn't matter if the direction shown is opposite to the 
 actual direction; the answer will always come out of any 
 correct calculation with the required minus sign..
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