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angela210793Best ResponseYou've already chosen the best response.1
I thought to multiply the first row with 1/3...dw:1329578934017:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
that would be a good idea angela :D
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
i can make the first element in the second row 0 but i can't go further :(
 2 years ago

bahrom7893Best ResponseYou've already chosen the best response.1
what's r? reduced row echelon?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
idk wht u call it...i'm asking for the range
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
why? multiply the first row with 4 and add to the third row to get 0 under
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
colA is the range of a matrix A right?
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
row reduce to determine your pivot points; and all columns with a pivot point define colA
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
I'm sorry i don't get it..wht is colA???
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
as far as I can tell, thats the american version of range of a matrix
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329579146175:dw
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
can you type in the rows? a b c d e f g h like that cause its hard to read .... well, nenands is a bit clearer
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329579294854:dw
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
your matrix I believe will simplify to 3 linearly independant column vectors; or less. that will tell us the range or span
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
:O:O:O:O How nenad?????? in the example my teacher has solved she has had the elements of the diagonal =1 :O
 2 years ago

amistre64Best ResponseYou've already chosen the best response.0
turning it into row reduced is extra work becasue the pivots dont change
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
no Angela I'm sure this is the solution...it's quite easy...do you know the procedure to get the rank of the matrix?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
i know the theory but i don't know how to use tht in practice _
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
how did u know u should have changed R1with R3???
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
well this is how you start...first you take a look at the first element of the matrix (first row and the first column)....if it's different from zero then you call it ''the pivot''. OK? Now you make zeros under that first pivot using muliplication with some number and adding to the row below....that's how you make the zeros under the first pivot. Then you look for another pivot...you follow the main diagonal and if it's different from zero then it's a second pivot and you make zeros under that number...you continue with this procedure until you're finished....the final rank is the number of elements on the main diagonal different from zero, so the number of pivots...in this case I have three pivots so the rank is 3
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
Hmmmm.....ok thanks guys :):)
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
>> rank([3 6 9 3;2 5 3 0;4 10 10 4]) ans = 3
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
Matlab says it's 3 also so your teacher is tripping :D
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
I'm really hopeless...:(:( thank you very much :) both of u :)
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
angela don't go...I can show you some examples so you can learn the procedure? I can give you some matrix and we'll work on it together OK?
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
ok here is one for begining:dw:1329580248289:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
now tell me what is the first element of this matrix and is it different from zero?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
since the first element f the matrix is 1 then the first element of R2 must be 0???
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
is the rank 1?? O.o
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
OK it's 1...so that is the first pivot...now do some operations to make 0 under that 1....the easiest way is to multiply the first row with 3 and to the second row...draw that so I can see OK?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329580611324:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
that's great...now since you made zero under that 1, the next step is to look for the next pivot(element different from zero) on the main diagonal....it's number 2....so you have to make zeros under that pivot...but since there are no more elements under that 2 the transformations are done and now you can read the rank of the matrix....the rank is the number of row where at least one element is different from zero, or you can count the number of pivots(elements on the main diagonal different from zero)...so what is the rank?
 2 years ago

RagingSquirrelBest ResponseYou've already chosen the best response.0
*Clicks on question thinking it's about the matrix* DANGIT
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
number of rows*
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
so the range is 2???
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
correct Angela!!! :D just to be clear here in Serbia we call it rang, but I read this material from the American matematicians and I'm sure they use the term ''rank''
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
haha :) can we work on some more examples pleaseeeee
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
of course....check this one:dw:1329580900431:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329581058847:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329581078055:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
no...we must make a deal here....it's very important the way you make zeros...you can't do it anyway you want...first you make the zeros under that 1. So multiply the first row with 2 and add to the second row....in the third row you already have zero so you don't touch that third row OK.? draw again...:D
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
no way :(:(dw:1329581327917:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
great it's correct now what is the next pivot you see?
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
that's my girl....now make zeros under that pivot....
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
xD just a thought...how abt R12R3???
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
tht won't work will it???
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
you don't touch the first row anymore...you made zeros under the first pivot, so you now operate with the second row....for example multiply the second pivot with 1/5 and add to the third row...
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329581919090:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329582143630:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
what is the third pivot now?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
5??? but there's no 0 under it O.o
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
that's right....that means no more transformations with the matrix so what is the rank?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
ur a genius xD :) Can i borrow ur brain???????
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
wait we must do one more :D
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329582383881:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
no problem :D OK Angela what is the first number you see?
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329582684252:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
OMG wait.... will i be the stupid girl who didn't get a single thing? :O:O:O
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
OK I hope we both agree that is unconvenient to perform ''zero making'' under that 13...so one of the possibilities is to exchange the first and the third column because the third column is filled with ''beautiful numbers '' for addition, multiplication etc do it
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
i was just going to ask if we could change C3 with C1 :)
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329582859078:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
now you work and I watch....:D
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329582907187:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329582876260:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329583007088:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
ahhhhaaaa...i just wanted ur confirmation ;) :P
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329583049393:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329583024634:dw
 2 years ago

angela210793Best ResponseYou've already chosen the best response.1
dw:1329583163929:dw
 2 years ago

nenadmatematikaBest ResponseYou've already chosen the best response.10
dw:1329583152017:dw
 2 years ago