## Precalculus (6th Edition) Blitzer

The force is a vector quantity. Let $\mathbf{u}$ and $\mathbf{v}$ be two force vectors. Formula to calculate the magnitude of the resultant is, $\mathbf{R}=\sqrt{{{\mathbf{v}}^{2}}+{{\mathbf{u}}^{2}}+2\mathbf{uv}\cos \theta }$ Here, $\mathbf{R}$ is the resultant force, $\theta$ is the angle between the two forces. So, the resultant force of two forces that each have a magnitude of one pound giving a vector whose magnitude is two pounds may or may not be possible. When both forces have the same direction, then the resultant force magnitude is two pounds; otherwise, the force will have a magnitude less than two pounds. Thus, the statement is false.