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sasogeekBest ResponseYou've already chosen the best response.0
I'm not sure what it is but this should give u a head start to what it means http://en.wikipedia.org/wiki/Column_space
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
wht i do not understand is how u make the transformations ...how do u know tht u change the places of xrow with y row...:(:(:(
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
To find the range of a matrix, just reduce it into row echelon form, and count the number of non zero rows. The number of non zero rows is the range of the matrix
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Oh! that thing, I am afraid you will have to figure that out yourself.
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But the key is to practice more and more reduction..
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
myself????? :O I've tried to...but i don't get it :((((
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I can help you out with a rough algorithm or something like "steps to perform", but still you will need to practice using that algorithm.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ok....can u explain me how u solve aproblem like this in twiddla??
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But before that let me make sure, you want me to teach you how to reduce a matrix into row echelon form, right?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So will I post an example? Or you will post yours
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
I'll post one dw:1329561659776:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
OK, now tell me what do you feel you must first do, and why?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
I have no idea at all :(((
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
OK, now you have to reduce it to something like dw:1329561739686:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
With zeros in all the empty spaces, right?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
yea tht's smth i know...
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So start by making the top left corner 1
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
You can do that by two methods, 1. Bring the lowest row to the top, 2. Divide the first column by 3
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
The first method seems easy
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I just exchanged row 1, and row 3
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
now u have to make 4 in the 3rd row 1 right?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Oh no, there is another, just let me write it fresh...
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
what happened to the 2 at the right corner?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
dw:1329562219705:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
dw:1329562156101:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Now again think, to make this new matrix similar to dw:1329562260442:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
.....you need to make the first element in the 2nd row zero.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i think u'll get a dw:1329562374039:dw won't you???
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
i.e. the circled element dw:1329562329966:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Sorry, you lost me.. but did you understand what I meant?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
yea yea i understood xD just tell me smth u make a diagonal =1 first and then 0 the other elements??
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So the next step would be to subtract 2 times row1 from row2. Could you follow me?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I mean do you feel why I am doing that?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
no.....don't u have to make the 4 in the third row 0 first???? O.o
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Which one? Can you circle it for me?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
dw:1329562705396:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
No, not at all. All you need to do is keep in mind the picture I gave you and proceed accordingly
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
By picture I meant, the matrix with 1 on the diagonals and 0s elsewhere.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
see.... wht u gave me is dw:1329562830135:dw and u have 4 ones in there(a diagonal with 4 elements) ...this isn't a square matrix to get tht....O.o and u said u'd do 1(ones) all the elements of the diagonal first then 0 the other elements......
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I am sorry, if you got that impression, but that is not exactly what I meant. I meant something of that sort that doesn't necessarily imply that it has to be 4 squared etc etc.
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I mean after reduction your picture will look something like that funny picture.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ahhhhhhhhhhhhhhhaaaaaaaaaaaaaaa......I'm sorry then :/ keep going....why would u multiply first row with 2 and then subtract it to row 2
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Just to make it look like that funny picture...
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
You will end up with something like dw:1329563098194:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
tht's wht i meant by this pic dw:1329563199692:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So what do you feel? Don't you feel that once you have got the first element in the first row 1, you should now start thinking about making the one just below it zero.
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I really don't understand that notation of yours, but do you understand mine?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
hahhaha...yea yea xD
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So just tell me, do you feel why I want to make the element just below 1, zero?
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
sorry to barge in but is it just any diagonal or just the diagonal that cuts through starting with the first number?
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
i mean the diagonal that must be all 1's....
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
yes yes I get this I'm gonna ask u smth just pls don't get angry....don't u have to make dw:1329563400348:dw this 1 first????
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Well, I never learnt it that way...:)
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
May be that is some other method.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ahhhhaaaaaaaaaa...ok then...u do wht u know...:)
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
math is a very clumsy road, u end up at the same destination
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i wasn't ending up anywhere with this problem :P
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
did u read the manual/instruction/algorithm to solving this problem?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
dw:1329563439879:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
wht did u do in there?????
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
OMG!!! I'm hopeless x( :(:(
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
wasn't the first element of the 2nd row supposed to b zero??? 2(2*1)=22=0
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Oh, does that thing look like 6, its actually 0..
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ahhhhaaaaa...ok then xD
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Next you need to turn the first element in the third row equal to zero
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
would tht be R33R1???
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
wait so u do 1 0 0 column by column, as in one column after the other?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
dw:1329563860051:dw
 2 years ago

sasogeekBest ResponseYou've already chosen the best response.0
1000 0100 0010 u should end up with this... right?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Exactly, but it may look a little different, but something similar to that.. P.S. angela210793 you typed the right notation
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ok....no now u have to make 3 in the 2nd column zero...how do u do tht???
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
First of all, can you check, if I did the calculations correct?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
dw:1329564323164:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i think so too O.o.....wht's next?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So the matrix which we now have is dw:1329564404847:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Now this particular problem was prepared in such a way, that we ended up with the 2nd and third row as equal
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But that is a nice case, it will not happen always.
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
In cases where it doesn't happen, you next intention would be to make the circled element equal to 1dw:1329564569074:dw
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Once the circle element is made 1, you will attempt to make all the elements below it equal to 0
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
can we multiply the second row with 1/7???
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Yes, that is exactly what you should have done if you were a computer.
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
can.. but it would be complicated
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
try avoiding fractions form..
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But being a human you can see, that you can subtract the second row from the third, and write it down in the third row
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
And that will make the whole of third row equal to zero
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
ohhhhhh...well i'm not a random person...I think like a computer :P
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
dw:1329564788814:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
7 is still 7...wht now?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
So now clearly you have two non zero rows, you can now say, that the range is 2
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
:O wht??? how was tht ..can u explain me once again please ???
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Just as I told you this was a nice problem. Real problems won't be like this. Here without any further reduction, it is visible, that no matter what you do, you can never make any of R2 or R1 zero... so there are two non zero rows. so t he range is 2
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
Hmmmmmmmmmmmm......ok.... Thank u very much :))))))))))) all of u, especially 2bornot2b :)) Gosh...How can u b so patient????
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
i dont understand what is range?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Here is a good problem
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i don't think it is good :P
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I meant it gives you the feel of what you need to do in real problems
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
ok now i understad what is range.. :)
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
And you can see in the reduction, things go in the same algorithm as I mentioned
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
so for the attachement given.. the range is 3 right?
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
ok now i understand.. but what it is for?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Something very deep xilem, its for actually solving linear equation.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
yea...why do we need these kind of problems in business? O.o
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But now it seems like a game
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
quoted earlier( wht i do not understand is how u make the transformations ...how do u know tht u change the places of xrow with y row...:(:(:( ) this is call transpose
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
Say I have 10 equations and each equations have 10 unknown, how are you going to solve it?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
so after having done all these things, I mean whatever you are studying, you will be able to solve linear equations without any effort.
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i know wht transposed matrix is....i didn't know why u changed x with y and why not x with z for example
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
But how did crammer invent that? This is all behind the scenes
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
i think all these things r unnecessary.....
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
I'm going to do my hws now...hopefully i'll solve them :) thnx a lot :)
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
hurmm... sorry can u show me example of that in cramers rule?
 2 years ago

2bornot2bBest ResponseYou've already chosen the best response.2
I said that you learn linear algebra to be able to solve linear equations, and cramers rule is just a product of linear algebra, so it directly is not a problem which can be used to show the application of cramers rule.
 2 years ago

xilem89Best ResponseYou've already chosen the best response.0
no i mean for the cramers rule (.i didn't know why u changed x with y and why not x with z for example ) can u show me example?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.2
this is how I've been taught cramer's rule dw:1329576915751:dw
 2 years ago
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