Normal vector from plane equation | Vectors and spaces | Linear Algebra | Khan Academy

Figuring out a normal vector to a plane from its equation

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[KingOfBeansAndSoup]

It's literally a 1 mark question I stumbled across. I look at the video time and it's 9 mins :(

Lads I'm going to cry

[ZzirDavS]

To find a normal vector in a plane though you need 2 vectors lying on the plane and take the cross product, so essentially you need three points.

[bahaatamer]

this is the 1000th time I stumble across a maths homework problem and you just saved me there! Thanks a ton for your free amazing lectures Mr. Khan, you are a really good tutor and I can find most of my problems solved here!

[gamingaddict]

the amount of times khan academy has saved my life is insane

[myonlynick]

there is a strategy in solving this problem. He aims for the dot product of 2 vectors, which are perpendicular to each other., that is all, that is the big picture in it. Also, perpendicular means he can have: <a> dot <n> = 0. He has <n> vector for granted and he tries to find <a> vector. You need 2 points sitting on the plane to define <a> = <p> - <p1> which is how we get the difference of 2 vectors.

[richardw-ip]

What is you are given the vector equation instead of the Cartesian equation for the plane? How would you get the normal then?

[elenaasi]

Oh my God this was so helpful.Thanks to Khan Academy for all of these videos, and toturials.

[dougkimzey]

An ok video to show the relationship of the equation of a plane to a normal vector to the plane. While already granular, more detail and a better example would reduce confusion.

[alexgs]

it was too theoretical maybe if real numbers were used it would have been easier to understand? usually you bang but i was lost

[Murf_Workshop]

Makes sense, I like your descriptions, Thank you very much.

[John-jkpo]

You can always trust Khan, he is amazing!

[Naruto]

Khan, you are so smart! Your tutorials are so helpful! :3 Thank you for doing what you do free of charge!

[asmitbhattacharya]

Finally found this after dozens of unhelpful videos by other channels
Thank you sir

[abebawtamene]

How can we produced the normal vetor when we solve the distance between point and the plane?

[MatthewThrone]

So what if you are given the equation of a plane and a point? How do you determine the vector equation for the line that passes through that point and is perpendicular to the plane?

[yonghuiliew]

I see the end of the playlist. Thank god

[souravpaul_per]

you are great...
thanks for your help❤️❤️

[MisterBinx]

So the chapter I just read is all about finding the tangent plane of a function of two variables. Just as I'm getting that down they throw this question at me with no examples given in the section. Why do the do that?

[batuamparh]

so that's what a normal vector of a plane looks like. this changes everything .

[Stratoscaster]

Normally, the x-axis is on the left, and the y-axis is in back. Or at least that is how I was taught