@redditknights5891 That professor was fired for helping the college embezzle funds like a few months ago. Prior to that they had been pulled multiple times due to a plethora of complaints from students who were unsatisfied with their teaching performances in labs and lectures. They also went on a 4 week hiatus during the term without alerting students. Talk your shit bro, still won't change the fact I got 93% in that module. To anyone else trying to educate themselves in the face of bad professors, keep going, you guys got this, you are on the right track by at least trying to teach yourself. You could be doing worse, like nothing at all, or worse again, shit talking others trying to learn.
@@republicraider8336 talking shit would be saying you're a not the brightest for waiting 4 weeks to go into youtube, all i said is if it took you 4 weeks to grasp a concept that, mind you, is heavily abundant in youtube..... your profesor is not fully the problem. college is not just about the professor, go out and do your own research or find tutoring.
@@redditknights5891 Either way, ur comment was unnecessary. He said it took his professor 4 weeks to explain. That's totally different from saying it took him 4 weeks to grasp the concept.
this linear algebra playlist of yours is the absolute best i've come across on the internet. Thank you for being so lucid and lending so much clarity to these (sometimes) abstract concepts. Are you making a differential equations playlist? Would love to see some ODE!!
I think it's important to note that a subspace must also contain the additive identity. In the case of vectors, it must contain the zero vector. Great video!
I am just doing video 33. I went to the last ones to check out whether the quality is going out, or the topics are too complex. But every video has only positive comment, which are clarly not farmed. IT's clear that the series is highly effective in teaching us the bascis. I am brushing up on math overall, and it feels great to be doing this course.
Note to viewers: The vector space V (as in the video) is also a subspace of itself. Hence, S does not have to be strictly smaller than V, as Dave slightly misleadingly stated in the introduction.
you are the best! i hope you continue to upload these videos because you are the best teacher i’ve had! i know that so many others you have helped would agree
Thank you! English is my second language and I had to watch your videos because I couldn't understand a single video of this topic in my native language.
bro you are the best at teaching this. I'm sooo grateful for your videos. Thank you so much! I was stressing out like crazy for my upcoming quiz until I came upon your teaching videos.
Think it still works cause the bottom will be positive and the top will be negative, in other words, the bottom is the negative of the top line which is negative. A bit confusing but I think the rule he stated was that the bottom line is the negative of the top line, not that the bottom line itself is necessarily negative.
the span of any number of elements of vector V is also a subspace of V a span is the smallest subspace of V that contains this set of elements span is important for describing vector spaces
I came here from Gunbuster- to see if subspace was a real term, and you could be speaking straight gobbledegook and I'd still think you're the smartest man on TH-cam.
No issue if c is negative. The original vectors can be any vectors in the form of [[x],[0],[-x]], where x is any real number. The multiplier c, can also be any real number. Multiplying any two real numbers together, also gets a real number, and x*c will still be the negative of -x*c.
Hey sir! I was just wondering, can the scalar for the 1st rule of Vector Spaces be a negative? If yes, wouldn't it make the matrix in the 1st question of Checking Comprehension not a subspace? Since the -b in the bottom row would turn positive
I'm not a professor but if you are talking about the 2bd question in last then if 2nd row if b becomes positive then b in first row will to -b thus form will remain same
i have a doubt, the video tells that the definition of linear combination is "some of all the elements of a vector space multiplied by some scalars" and the definition of span is given as "set of all possible linear combinations". but in the example, only one possible linear combination of the vector space is considered and given the name span, shouldn't the span be a set of v1 v2 and v3 multiplied by diff series of scalars, why just stop with a b and c? x(v1) + y(v2) + z(v3) should also be a linear combination of the space. and the set of V multiplied by a,b,c and x,y,z should be called a span?
c can be any real number, remember it's a scalar, so it can be negative. thus, it will still work as the first component of the x vector has the opposite sign of the third component of the x vector, so it still satisfies this closure property
@@Christian-mn8dh Think of form as meaning pattern. A vector in the form of [[x],[0],[-x]] means that you can put any (real in this case) number in the position of the x, in both the first and final entry of this vector. So this means that [[4], [0], [-4]] as well as [[-6], [0], [-6]] are vectors of this form. They have something in common, in that their first and final entries are negatives of each other, and they have zero for the middle entry. Note that the nested brackets is my way of indicating the vertical matrix, in an inline text description. Think of the innermost brackets as individual rows, and the outermost bracket as the full matrix of those rows. In this case, there's just one entry per row, since vectors in linear algebra are considered vertical matrices.
well, you assume a and b to be constants that are also real numbers. so the span, as a result, will be a real number, as you're not dealing with any variables here...hope this helps :)
I didnt understand the part where span of V is the smallest subspace of V. How come? The a1V1+a2V2+a3V3 (if linearly independent) is the entire R3 right?
Omg , I’m gonna subscribe you , my prof is terrible I don’t understand what tf he talking about , after this video , I was kinda understand the theory and concept
here is an interesting idea, since points in cartesian space are just sums of the i-hat and j-hat basis vectors with real coefficients technically speaking all of the 2-d coordinates system is simply span(i_hat,j_hat). Similarily the 3-d cartesian system is just span(i_hat,j_hat,k_hat)
What if sub space doesn’t include identity O but satisfies closure . It’s not a vector space is it? Still a subspace? If so not every subspace is vector space. Am I missing something ?
First we check for identity 0 so if the sub space doesn't include identity 0 then it is not a subspace. and if it includes identity 0 then we check for closures.
The R refers to real numbers. The 2x2 refers to 2x2 square matrices. Putting it together, it refers to the set of all square matrices with 2 rows and 2 columns that contain any real number in each of the 4 entries.
Don't know if you will ever see this comment, but thank you. You are getting me through my college linear algebra class. My teacher is so bad at explaining things, and you make it so simple to understand.
No professor of mine is able to compete with your brilliant explanations. Something seemingly complicated made so simple.
i guess it is pretty randomly asking but does anyone know a good place to watch newly released series online?
@@damiankarsyn9653 no
@@damiankarsyn9653 what series?
@@andrewkorsten2423 Fourier series?
You've just explained in 5 minutes what took my professor four weeks to half explain. Thank you.
If you didn't get it in 4 weeks maybe your professor isn't the problem
@redditknights5891 That professor was fired for helping the college embezzle funds like a few months ago. Prior to that they had been pulled multiple times due to a plethora of complaints from students who were unsatisfied with their teaching performances in labs and lectures. They also went on a 4 week hiatus during the term without alerting students. Talk your shit bro, still won't change the fact I got 93% in that module.
To anyone else trying to educate themselves in the face of bad professors, keep going, you guys got this, you are on the right track by at least trying to teach yourself. You could be doing worse, like nothing at all, or worse again, shit talking others trying to learn.
@@republicraider8336 talking shit would be saying you're a not the brightest for waiting 4 weeks to go into youtube, all i said is if it took you 4 weeks to grasp a concept that, mind you, is heavily abundant in youtube..... your profesor is not fully the problem. college is not just about the professor, go out and do your own research or find tutoring.
@@redditknights5891 Either way, ur comment was unnecessary. He said it took his professor 4 weeks to explain. That's totally different from saying it took him 4 weeks to grasp the concept.
I literally have a midterm in 2 hours you are a godsend
i have a meeting with ur mom in like 2 minutes
@@micoluk9446 how was it
@@DARTH-R3VAN just like with ur mom
Yup we’re fucked
@@tomatrix7525 like our moms
I really appreciate that you are speaking so clearly! It makes your videos easy to follow despite my hearing loss:)
this linear algebra playlist of yours is the absolute best i've come across on the internet. Thank you for being so lucid and lending so much clarity to these (sometimes) abstract concepts. Are you making a differential equations playlist? Would love to see some ODE!!
Yes I've been meaning to do that for a while! Just looking for the right writer.
@@ProfessorDaveExplains pls do PDE also (love from india )
@@ProfessorDaveExplainsdo you still plan on doing this?
I think it's important to note that a subspace must also contain the additive identity. In the case of vectors, it must contain the zero vector. Great video!
I am just doing video 33. I went to the last ones to check out whether the quality is going out, or the topics are too complex. But every video has only positive comment, which are clarly not farmed. IT's clear that the series is highly effective in teaching us the bascis. I am brushing up on math overall, and it feels great to be doing this course.
Note to viewers:
The vector space V (as in the video) is also a subspace of itself.
Hence, S does not have to be strictly smaller than V, as Dave slightly misleadingly stated in the introduction.
you really a gem. i cannot express enough gratitude for your videos, and im certain im not the only one to feel this way. thank you!
you are the best! i hope you continue to upload these videos because you are the best teacher i’ve had! i know that so many others you have helped would agree
You have made algebra easier for me compared to our boring lecturers. Thanks a lot. Much love ❤️ from Nigeria 🇳🇬
Seriously 🥺
Thank you! English is my second language and I had to watch your videos because I couldn't understand a single video of this topic in my native language.
5:12 what if we multiplied by a negative scalar? Would we still get a matrix in the specified form?
It would not match the form of the 2x2 matrix and therefore not be a subspace. I agree with your logic.
bro you are the best at teaching this. I'm sooo grateful for your videos. Thank you so much! I was stressing out like crazy for my upcoming quiz until I came upon your teaching videos.
Thank you for making it simple and easy to understand!
in 5 minutes , you have perfectly explained what my professor failed to teach us for 4 hours, much appreciated
I did love this vid so much. It helped me to understand the basis of vector spaces which had taken me a lot of time to learn in the class.
What if c is negative?
exactly what I was thinking
Me too😅
Think it still works cause the bottom will be positive and the top will be negative, in other words, the bottom is the negative of the top line which is negative. A bit confusing but I think the rule he stated was that the bottom line is the negative of the top line, not that the bottom line itself is necessarily negative.
Still it will be a vector space because say x=-2 (-2,0,2) or or if x=2 then also(2,0,-2) both do belongs to S i.e (x,0,x)
the span of any number of elements of vector V is also a subspace of V
a span is the smallest subspace of V that contains this set of elements
span is important for describing vector spaces
I came here from Gunbuster- to see if subspace was a real term, and you could be speaking straight gobbledegook and I'd still think you're the smartest man on TH-cam.
Wish I had a professor like you
great professor just teaching complicating things with such ease
For closure under addition, do the vectors that are added to vectors in a subspace have to be part of the subspace themselves?
yes
Thank you so much!
Thanks for ur quality learning style Professor.Thanks from Turkey.
Why the first question of the comprehensive is true? Could someone explain it please?
2:20 is it really closed under scalar multiplication? what if c is negative???
No issue if c is negative. The original vectors can be any vectors in the form of [[x],[0],[-x]], where x is any real number. The multiplier c, can also be any real number. Multiplying any two real numbers together, also gets a real number, and x*c will still be the negative of -x*c.
Hey sir! I was just wondering, can the scalar for the 1st rule of Vector Spaces be a negative? If yes, wouldn't it make the matrix in the 1st question of Checking Comprehension not a subspace? Since the -b in the bottom row would turn positive
I'm not a professor but if you are talking about the 2bd question in last then if 2nd row if b becomes positive then b in first row will to -b thus form will remain same
Clear explanation, carry on.
Thank you for saving my semester professor much love from Kenyatta university ( Nairobi Kenya)
argh thank you so much i was having a hard time understanding all this. The video is so good i had to watch it 3 time lol
nice explanation Prof. Dave
Can you please explain what you meant by 'Any sum of these elements" in 3:20
I know it’s too late but anyways😂, it just means the sum of the elements when they have been multiplied by a1 , a2 and so on
Praying Tanaka is so lucky to have found you Professor Dave.
What are the difference between a Span and a Subspace?
I have a midterm in 3 hours 😩 thank you so much
Wow wonderful explaination
You are really explaining brillians as we are always doing right in checking comprehension
i have a doubt, the video tells that the definition of linear combination is "some of all the elements of a vector space multiplied by some scalars" and the definition of span is given as "set of all possible linear combinations". but in the example, only one possible linear combination of the vector space is considered and given the name span, shouldn't the span be a set of v1 v2 and v3 multiplied by diff series of scalars, why just stop with a b and c? x(v1) + y(v2) + z(v3) should also be a linear combination of the space. and the set of V multiplied by a,b,c and x,y,z should be called a span?
a, b and c aren't fixed scalars.
2:00 why we are checking its closed or not, since its a subset of vector space..
Confused!
we are trying to check if it is indeed a subset , thats why
thank you.
2:28 what if c was -1
Scalar positive integer
@@bigilpandi7722 wrong
c can be any real number, remember it's a scalar, so it can be negative. thus, it will still work as the first component of the x vector has the opposite sign of the third component of the x vector, so it still satisfies this closure property
@@multitude1337 so what does 'form' really mean? im confused
@@Christian-mn8dh Think of form as meaning pattern. A vector in the form of [[x],[0],[-x]] means that you can put any (real in this case) number in the position of the x, in both the first and final entry of this vector. So this means that [[4], [0], [-4]] as well as [[-6], [0], [-6]] are vectors of this form. They have something in common, in that their first and final entries are negatives of each other, and they have zero for the middle entry.
Note that the nested brackets is my way of indicating the vertical matrix, in an inline text description. Think of the innermost brackets as individual rows, and the outermost bracket as the full matrix of those rows. In this case, there's just one entry per row, since vectors in linear algebra are considered vertical matrices.
Sir, multiply vector x with any negative constant value. Then, will the resultant vector x belong to the set S?
same doubt
Awesone very nice explanation
English is my third language, and you still explain better than my professors in my mother tounge
Holy crap I just understood vectorspaces in less time than my professor did in 3 hours.
in 5:09 (2), can their span be in real number instead of a & b?
well, you assume a and b to be constants that are also real numbers. so the span, as a result, will be a real number, as you're not dealing with any variables here...hope this helps :)
I already miss your long hair
simon dx I agree
So the " C " is considered postive here?
I didnt understand the part where span of V is the smallest subspace of V. How come? The a1V1+a2V2+a3V3 (if linearly independent) is the entire R3 right?
You saved me!
TY professor!
Thanks
Very nice,Thx
WOW , u made everything clear for me thank u so much :)
Sağol professor, canın sağ olsun. Çox sadə izah edirsən
Sir in Example of subspace what if we take the value of scalar as negative then the 1st property will not be held . Please help me with my doubt.
How
Thank you it is help full lecture!!!!
Omg , I’m gonna subscribe you , my prof is terrible I don’t understand what tf he talking about , after this video , I was kinda understand the theory and concept
Thank you so much. By definition would a vector space be a (very useless) subspace of itself?
Know it's too late but for anyone with a similar question: V is in itself a subspace of V.
@@AEPPLE_MUSIC Makes sense
YES OFCOURSE! IT WOULD BE. 🙂
Multiplying zero scalar to a vector will yield zero result,
So, in case of subspace, we could say that it is closed for scalar multiplication?
c = 0 makes me think of another question. If c = 0, then the vector is [0,0,0]. which means it's not maintaining the [x,0,-x] form??? idk. pls help
what if you had used -1 as a scalar to multiply?
i am facing the same issue
here is an interesting idea, since points in cartesian space are just sums of the i-hat and j-hat basis vectors with real coefficients technically speaking all of the 2-d coordinates system is simply span(i_hat,j_hat). Similarily the 3-d cartesian system is just span(i_hat,j_hat,k_hat)
Every subspace of R5 that contains a nonzero vector must contain a line. Is this statement true?
yes!
2:09, why is it “-(cx)”?
c * (-x) is -cx
just to illustrate that it's some number in the form -x better
Multiplication of real numbers is associative and commutative, so you can rearrange the parentheses and negative sign, however you prefer.
better than my professor
What if sub space doesn’t include identity O but satisfies closure .
It’s not a vector space is it? Still a subspace?
If so not every subspace is vector space. Am I missing something ?
First we check for identity 0 so if the sub space doesn't include identity 0 then it is not a subspace. and if it includes identity 0 then we check for closures.
thanK you so much.
I don't understand R 2*2 Could you explained it
he made a video called understanding vector space
The R refers to real numbers. The 2x2 refers to 2x2 square matrices. Putting it together, it refers to the set of all square matrices with 2 rows and 2 columns that contain any real number in each of the 4 entries.
PLEASE MAKE LECTURES ON REAL ANALYSIS
i have a midterm tomorrow thx
what if one of a,b,c,d is a complex number???
teşekkürler, iyi geldi
awesome
High asf, endterm in 2 days and I understand everything 😂
Great ! Thanx! 😂
Don't know if you will ever see this comment, but thank you. You are getting me through my college linear algebra class. My teacher is so bad at explaining things, and you make it so simple to understand.
Same with my Linear Algebra Course. This is helping a lot.
Can someone explain #2 to me?
Watching 10 min before exam
Midterm in 20 minutes 💀💀
Why the hell am I getting "Feet finder" ads on TH-cam?? And on math tutorials of all places???
Hrs of lec
Private videos ??
they'll be released one per week
Savior
french: Span is written as Vect
wish I could pay my tuition to you instead : (
❤
didnt understand a thing
Sir Hindi