Use the dot product to find the magnitude of u if $\mathbf { u } = \langle 3,2 \rangle$
A) $\| \mathbf { u } \| =$ $2 \sqrt { 13 }$
B) $\| \mathbf { u } \| =$ $\sqrt { 13 }$
C) $\| \mathbf { u } \| = 6$
D) $\| \mathbf { u } \| = 5$
E) $\| \mathbf { u } \| = 7$

Question

Quizplus · Accepted Answer

The magnitude of a vector $\mathbf{u} = \langle a, b \rangle$ is given by $\| \mathbf{u} \| = \sqrt{a^2 + b^2}$. For $\mathbf{u} = \langle 3, 2 \rangle$, $\| \mathbf{u} \| = \sqrt{3^2 + 2^2} = \sqrt{9 + 4} = \sqrt{13}$.

Use the Dot Product to Find the Magnitude of U u=⟨3,2⟩\mathbf { u } = \langle 3,2 \rangleu=⟨3,2⟩

Use the Dot Product to Find the Magnitude of U $\mathbf { u } = \langle 3,2 \rangle$