The Vector Dot Product

We learned how to add and subtract vectors, and we learned how to multiply vectors by scalars, but how can we multiply two vectors together? There are two ways to do this, and one of them is called the dot product. Let's learn how to find the dot product of two vectors now!
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I'm now ready for my exams...
Thanks to you💜

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this guide is absolutely perfect. I was lost in class for a week and this helped me catch up in less than 7 minutes

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Perfect timing! Im doing this in my physics class

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thanks, taking quantum mechanics and wasn't paying attention to the plus sign during lecture. now things make more sense. Scalar Product is Dot Product to find a Scalar Value.

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Thanks for the mathematical warmup
This will be very helpful for the graphical/game dev stuff with C

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Kudos sir👍

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Dev. I am impressed. Short and clear.

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The BEST answer i got from all of the videos I have watched.

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Thank you! Very well explained

[@ItCanAlwaysGetWorse]

Wonderful explanation. Very clear and succinct.
I would only add the 2d visual notion that "vector dot product" (of two vectors) is obtained by multiplying the length of either vector by the "projection" of one vector over the other (think of laying the angles vectors flat on a table, and having a lamp illuminating from "above". You would multiply the length of the vector laying flat by the length of the shadow of the companion.).

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🙏 thankyouu!! This is such a well constructed and insightful video - probs the best I've seen on this topic.

[@liamcraft9844]

I knew how to do this, but not why. Thanks for the lightbulb moment!

[@TheRojo387]

Btw Dave, I have cracked vector rotation, relying entirely on scalar and dot products. My solve can also be extended to higher dimensions, as I also standardise with the right-hand rule.
I also note that you can find the angle by looking for one co-ordinate on a unit circle, and measure the area beneath it and add the triangle adjacent to it and with its opposite point at the origin, and multiply all by two, to get the answer in radians.
But if degrees are your fancy, you gotta multiply instead by 90/π!
Or…you could just use a protractor. Et voilà; no calculator needed!

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Thank u sir for ur video.... I'm now able to do it before anyone... even my teacher... thanks again 🤗

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I watched other videos before this one ,and trust me this is the best and the most comprehendable

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extraordinary explanation
thanks

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Literally watched this during lecture. Explained everything that professor couldn't in 2 hrs in just 6 mins.

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I have been searching for so long for some details like this

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Very useful bro!!!

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Great video, thank you! Haven't done this since the 80s.

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Good stuff - breaks it down better than my uni professors

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You are better than my physics teacher❤️👑

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Bless you sir. Studying for my high school math teaching cert and it’s gone from 0 to calculus in one chapter.

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Thank you Professor...I am doing 3d graphics engineering and needed an explanation on why the guy in the video was using the .product over the lengths of a and b to determine if an angle was withing 90°

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You are the one, Sir.

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Thank you professor. You made dot product as a pice of cake to me:) love your explanation

[@kaluvanhariharan4256]

professor, very informative lecture. Thanks.
Can you post a video for understanding Eigen Vector and Eigen value?

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was never taught this in school but need it now

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It's last night before the exam and then I found u... much luv❤

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There is no way I would have been able to get this far in school without RUclips

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Everytime I see his face I can already hear "He knows a lot about a kinds of stuff. Professor. Dave. Explains." 😂❤😊

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thank you kind sir, online class isvery hard

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Superb!

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good job man :D

[@parunarvekar9132]

Thank you very much

[@omarfaruk2842]

Why we use cosine to get dot product of two angle vector?

[@nyinanajulu4905]

Is it possible to get them broken down into topic segments?