Calculus 3: Vector Calculus in 3-D (11 of 35) Dot Product in 3-D: Find thetha=?

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In this video I will find the dot product=? of A=7i+3j+5k and B=-8i+4j+2k, and the angle between vector=? A and B.
Next video in the series can be seen at:
• Calculus 3: Vector Cal...

[@virunanadun4323]

why we don't get the 3 rd quadrant angles as our answer

[@MichelvanBiezen]

Negative angles is a mathematical concept when related to the cartesian coordinate system In the real world negeative angles don't exist. We are simply calculating the angle between two vectors. (Just like there are no negative angles in a triangle)

[@kina4288]

i take that these two are position vectors, otherwise there should be two possible answers according to the way they intersect. How can we tell if a given vector is position vector or a displacement vector.

[@ExteminatorHackerWithCookies]

Thanks Sir

[@MichelvanBiezen]

You are welcome.

[@kasmaalhareer9470]

thanks sir