Let the vector be ( vec{v} = langle x, y rangle )
Use the formula ( |vec{v}| = sqrt{x^2 + y^2} )
For a 3D vector ( vec{v} = langle x, y, z rangle ), use ( |vec{v}| = sqrt{x^2 + y^2 + z^2} )
Square each component
Add the squared values
Take the square root of the sum
The result is the magnitude of the vector