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Find the indicated quantity, given u = (4, -9), v = (-4, -7).Step 4 of 4: Find (u • v)4v.

Find the indicated quantity, given u = (4, -9), v = (-4, -7).Step 4 of 4: Find (u-example-1

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Answer:


\begin{equation*} \langle-1316,-2303\operatorname{\rangle} \end{equation*}

Explanation:

Given the vectors:


\begin{gathered} u=\langle4,-9\rangle \\ v=\langle-4,-7\rangle \end{gathered}

The dot product of u and v is calculated below:


\begin{gathered} u\cdot v=4*-4+-9*-7 \\ =-16+63 \\ =47 \end{gathered}

Therefore:


\begin{gathered} (u\cdot v)4v=47*4\langle-4,-7\rangle \\ =329\langle-4,-7\rangle \\ =\langle-4*329,-7*329\rangle \\ =\langle-1316,-2303\operatorname{\rangle} \end{gathered}

The indicated quantity is:


\begin{equation*} \langle-1316,-2303\operatorname{\rangle} \end{equation*}

User Subin Jacob
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