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Let u = <-5, -9>, v = <6, 8>. Find -8u - 2v. (2 points)

<52, 88>

<-8, 2>

<112, -28>

<28, 56>

User MLow
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1 Answer

4 votes

Multiplying a vector by a scalar means to multiply each coordinate of the vector by said scalar:


u = (-5, -9) \implies -8u = (40, 72)


v = (6, 8) \implies 2v = (12, 16)

Vectors are summed/subtracted by summing/subtracting correspondent coordinates:


-8u-2v = (40, 72) - (12, 16) = (40-12, 72-16) = (28, 56)

User Nahuel
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