A
Step-by-step explanation:
90 Degree Rotation. When rotating a point 90 degrees counterclockwise about the origin our point A(x,y) becomes A'(-y,x). ...
180 Degree Rotation. When rotating a point 180 degrees counterclockwise about the origin our point A(x,y) becomes A'(-x,-y). ...
270 Degree Rotation.
Answer:

Step-by-step explanation:
Given


Required:
Calculate the angle between u and v
The angle
is calculated as thus:

For a vector


becomes




For a vector


So;






So:






Take arccos of both sides





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<em> (approximated)</em>