Calculate the distance $d$ from $\vec{y}$ to the straight line through $\vec{u}$ and the origin

$\begingroup$

Background

Let $$\vec{y}= \left[ {\begin{array}{cc} 5 \\ 1 \\ 10 \\ \end{array} } \right]$$

and $$\vec{u}=\left[ {\begin{array}{cc} -7 \\ 3 \\ -3 \\ \end{array} } \right]$$

Calculate the distance $d$ from $\vec{y}$ to the line through $\vec{u}$ and the origin.

My work so far

Using the formula

$$d=\left|\vec{y}-\frac{\vec{y}\cdot\vec{u}}{|\vec{u}|}{\vec{u}}\right|$$

and plugging in

$$d=\left|\begin{pmatrix}5\\1\\10\end{pmatrix}-\frac{-62}{67}\begin{pmatrix}-7\\3\\-3\end{pmatrix}\right|$$

and then calculating

$$\frac{11\sqrt{38}}{\sqrt{67}}=8.284133.$$

Am I on the right track here? Or, where did I go wrong?

$\endgroup$ 5 Reset to default

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

You Might Also Like