What is the dot product of $< - 1, 1, 2 >$ $<-1,1,2 >$ and $< - 2, - 8, - 1 >$ $<-2,-8,-1 >$ ?

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What is the dot product of $< - 1, 1, 2 >$ $<-1,1,2 >$ and $< - 2, - 8, - 1 >$ $<-2,-8,-1 >$ ?

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Answer 1 · 2016-02-07T16:23:14

$a \cdot b = - 7$ $a*b=-7$

Explanation:

$a = a_{_} i + a_{j} + a_{k}$ $a=a__i +a_j+a_k$
$b = b_{i} + b_{j} + b_{k}$ $b=b_i+b_j+b_k$
$a \cdot b = a_{i} \cdot b_{i} + a_{j} \cdot b_{j} + a_{k} \cdot b_{k}$ $a*b=a_i*b_i+a_j*b_j+a_k*b_k$
$a \cdot b = (- 1 \cdot - 2) + (1 \cdot - 8) + (2 \cdot - 1)$ $a*b=(-1*-2)+(1*-8)+(2*-1)$
$a \cdot b = 2 - 8 - 1$ $a*b=2-8-1$
$a \cdot b = - 7$ $a*b=-7$

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What is the dot product of $< - 1, 1, 2 >$ $<-1,1,2 >$ and $< - 2, - 8, - 1 >$ $<-2,-8,-1 >$ ?

1 Answer

Explanation:

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What is the dot product of <−1,1,2><-1,1,2 > and <−2,−8,−1><-2,-8,-1 > ?

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Explanation:

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What is the dot product of $< - 1, 1, 2 >$ $<-1,1,2 >$ and $< - 2, - 8, - 1 >$ $<-2,-8,-1 >$ ?