Appendix:
Direction and sign of one-dimensional vectors and angles
Here, we will explain the definitions of directional dimensions and angles used in the diagrams in each chapter.
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Direction and sign of one-dimensional vectors
The one-dimensional vector notation is defined as follows:
・ In the up and down directions, the scalar of an upward vector is a positive value, and the scalar of a downward vector is a negative value.
・In the left-right direction, the scalar of a vector pointing to the right is a positive value, and the scalar of a vector pointing to the left is a negative value.
・Multiplying the scalar quantity of each vector by -1 means swapping the start and end points of the vector and reversing its direction.
If the scalar quantity of a vector is A, and A (+) > 0 and A (-) < 0, the relationship between the scalar quantity and the vector is shown below.
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Direction and sign of angles
The direction and sign of the angle are defined as follows:
・The scalar value of an angular rotation in the counterclockwise direction is positive, and the scalar value of an angular rotation in the clockwise direction is negative.
・Multiplying the scalar quantity of each angle by -1 means swapping the start and end points of the angle and reversing its direction.
When the scalar quantity of a certain angle is φ, and φ(+)>0 and φ(-)<0, the relationship between the direction of the angle and the scalar quantity is as follows:
