Definition: Let [math]OP^{\rightarrow}=\left(x,y,z\right)[/math] be any three dimensional vector. Then its absolute value or modulus is given by OP = [math]\mid[/math][math]OP^{\rightarrow}[/math][math]\mid[/math] = [math]\sqrt{ }[/math](x[sup]2[/sup] +y[sup]2[/sup] +z[sup]2[/sup] ) as shown in the figure.