矢量的模

The magnitude of a vector is essentially the length of that vector. We can do this by finding the composition of the given vector (getting the horizontal and vertical components of the vector) and using the Pythagorean Theorem.

For example, let us define a vector V = <a,b> as a vector with horizontal component a and vertical component b.

We can say that this vector V has magnitude $\sqrt{a^2+b^2}$.

Magnitude is simply length, so the magnitude of a vector is the length of the vector. To find the magnitude (denoted by $|\vec{v}|$) where $\vec{v}=(a,b)$ we use Pythagorean Theorem/Distance Formula: $|\vec{v}|=\sqrt{a^2+b^2}$.

Here's a worksheet to practice your skills: worksheet

To convert a vector into component form, subtract the coordinates of one of the vertices from both vertices so that there is a vertex at the origin.

Good luck!