Itâs a cost-benefit analysis: If it costs you 3 hours weekly to do the wash, but costs you $30 to send it out â that is $10 per hour. But if you bill more than that at your business â or stand to get a raise if you use those three hours to learn new skills, earn a degree, etc., it is worth the investment.
Coordinate Rules for Rotations. In general, we can state the following coordinate rules for (counterclockwise) rotations about the origin: For a rotation of 90o: (x, y) --> (ây, x) For a rotation of 180o: (x, y) --> (âx, ây) For a rotation of 270o: (x, y) --> (y, âx)
-sin(a) cos(a) for any clockwise rotation of a degrees about the origin. If we let a=90 degrees we have. [0 1] as the first row and [-1 0] as the second row.So the matrix is: |0 1|. |-1 0|. Call that matrix M. So a point p= (x,y) can be multiplied by M as follows Mp=p' where p' is the rotated point.sin(a) cos(a) for any clockwise rotation of a degrees about the origin. If we let a=90 degrees we have. [0 1] as the first row and [-1 0] as the second row.