Question

Write EF as the sum of unit vectors E(-5,-2,4) and F( 6,-6,6).

a. 11t-4j+6k
b. 11t-4j+2k
c. 11t-6j+2k
d.6t-4j+2k

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Answer 1

A vector is the difference of two points.

EF = F-E = (-5 - 6, -2 - -6, 4 - 6) = (-11, 4, -2)

In terms of unit vectors that's

-11i + 4j - 2k

Ah, they did EF=E-F. I do it the other way, EF=F-E, which I think is more standard. Let's roll with it.

EF = E - F = 11i - 4j + 2k

Answer: B