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)
Mathematically, a rotation is a rigid body movement which, unlike a translation, keeps a point fixed. This definition applies to rotations within both two and three dimensions (in a plane and in space, respectively.) All rigid body movements are rotations, translations, or combinations of the two. A rotation is simply a progressive radial orientation to a common point. That common point lies within the axis of that motion. The axis is 90 degrees perpendicular to the plane of the motion. If the axis of the rotation lies external of the body in question then the body is said to orbit.