Calc 3 vectors: a = < 6, -2, -1 >, b = < 2, 5, 2 > (parallel or orthogonal?)

[gennkill]

Calc 3 vectors: a = < 6, -2, -1 >, b = < 2, 5, 2 > (parallel or orthogonal?)

Determine if the following vectors are parallel, orthogonal, or neither.

. . .\(\displaystyle \mbox{(a) }\, \overrightarrow{a}\, =\, \langle 6,\, -2\, -1 \rangle,\, \overrightarrow{b}\, =\, \langle 2,\, 5,\, 2\rangle\)

How do i know if my answer is parallel or orthogonal?? I'm confused. Also i'm unsure how to calculate this.

 

[mmm4444bot]

Determine if the following vectors are parallel, orthogonal, or neither.

. . .\(\displaystyle \mbox{(a) }\, \overrightarrow{a}\, =\, \langle 6,\, -2\, -1 \rangle,\, \overrightarrow{b}\, =\, \langle 2,\, 5,\, 2\rangle\)

How do i know if my answer is parallel or orthogonal?? I'm confused. Also i'm unsure how to calculate this.

If the dot product of two vectors is zero, then the vectors are orthogonal.

Do you know how to calculate the dot product of your vectors above? You can google it. :cool:

 

[HallsofIvy]

And two vectors are "parallel" if and only if one is a multiple of the other. Here, 6 is 3 times 2 but -2 is not 3 times 5.

Surely your text book include that?