What is the dot product of $(-300i + 200j - 150k)$ and $(i + j -7k)$ ?

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Answer 1 · 2016-12-02T20:37:47

$A*B=950$

$A=(ai+bj+ck)$

$B=(di+ej+fk))$

$A*B=a*d+b*e+c*f$

$A*B=((-300*1)+(200*1)+(-150*(-7)))$

$A*B=-300+200+1050$

$A*B=950$

What is the dot product of (-300i + 200j - 150k) (-300i + 200j - 150k) and (i + j -7k)(i + j -7k)?