Question

Let u = <-5, -3>, and let v = <-6, -1>. Find -3u + 5v.

Please assist me, I'm quite bad at these. ^-^;
25 Points to earn.

Answer 1

`\bf \begin{cases} u=\ \textless \ -5,-3\ \textgreater \ \\ v=\ \textless \ -6,-1\ \textgreater \ \end{cases} \\\\\\ \begin{cases} -3u\implies \ \textless \ -3\cdot -5~~,~~-3\cdot -3\ \textgreater \ \implies &\ \textless \ 15,9\ \textgreater \ \\\\\\ 5v\implies \ \textless \ 5\cdot -6~~,~~5\cdot -1\ \textgreater \ \implies &\ \textless \ -30,-5\ \textgreater \ \end{cases}\\\\ -------------------------------\\\\ -3u+5v\implies \ \textless \ 15,9\ \textgreater \ ~~+~~\ \textless \ -30,-5\ \textgreater \ \\\\\\ \ \textless \ 15+(-30)~~,~~9+(-5)\ \textgreater \ \implies \ \textless \ -25~~,~~4\ \textgreater \`

notice, you simply do the "scalar multiplication" first, and then do the addition.