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Find the indicated quantity, given u = (0, -7), v = (5, -8).Step 4 of 4 : Find (u • v)4v.

Find the indicated quantity, given u = (0, -7), v = (5, -8).Step 4 of 4 : Find (u-example-1
User Yoana
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1 Answer

7 votes

Recall that:


\begin{gathered} \cdot=xv+yw, \\ a=. \end{gathered}

Then:


\begin{gathered} u\cdot v=0*5+(-7_)*(-8)=0+56 \\ =56. \end{gathered}

Then:


(u\cdot v)4v=56*4<5,-8>.

Simplifying the above result we get:


\begin{gathered} 56*4<5,-8>=224<5,-8>=<224*5,224*(-8)> \\ =<1120,-1792>. \end{gathered}

Answer:


\begin{equation*} <1120,-1792>. \end{equation*}

User Alec Wenzowski
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4.7k points