The vector is zk. We know that = xi + yj. The vector , being the sum of the vectors and , is therefore. This formula, which expresses in terms of i, j, k, x, y and z, is called the Cartesian representation of the vector in three dimensions.

A 3D vector is a line segment in three-dimensional space running from point A (tail) to point B (head). Each vector has a magnitude (or length) and direction.

The components of the vector specify the displacement from the tail to the tip. The z axis, which is not shown, comes out of the page, toward you. A quantity that is represented by a single number is called a scalar. A scalar quantity does not have a direction.

I know the vector equation of a line is r×v=a×v, where r is the position vector of a point on the line, a is a fixed point on the line, and v is a direction vector for L.

In computer science, a 4D vector is a 4-component vector data type. Uses include homogeneous coordinates for 3-dimensional space in computer graphics, and red green blue alpha (RGBA) values for bitmap images with a color and alpha channel (as such they are widely used in computer graphics).

People, like any other object that we know of, are made of particles that move in 4-dimensional spacetime. Therefore, although a person (or any other object) occupies only a 3-dimensional volume in space, its path through spacetime would look like a 4-dimensional volume.

3D objects will not be existed without 2D surfaces. To make a cube, we need 6 surfaces with same 2D dimensions. An 2D object still can move in either x-axis, y-axis or z-axis. It’s just like what objects you have modelled.

These point particles are 0-dimensional objects, as they don’t have a size, and they do have mass. So theoretically, you could construct a technically 2-dimensional object out of points, and it would have mass.