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Linear Algebra Exercise Class - Benedetta Cavalli - Shared screen with speaker view
Nicolas Mrowietz
01:28
yes
Marc Foertig
01:28
Yes
Michelle
01:30
yes
Petz
02:13
like last time please
Nicolas Mrowietz
02:15
start with Sheet 11
Albina Kudoyarova
02:15
sheet 11, please
Michelle
02:16
sheet 11 :)
yael
02:17
Sheet 11
Tesii
02:18
I would like to start with sheet 11
nikolaihorozov
06:22
yes
Tesii
06:23
no...
Tesii
10:55
thanks!
Nicolas Mrowietz
17:09
So if Q(x) is equal to Zero is it Semi-positive-definite or Semi-negative-definite? Because 0 is included in both definitions...
Nicolas Mrowietz
18:58
ah okay, thanks!
Tesii
20:30
yes
nikolaihorozov
20:30
i think so
nikolaihorozov
20:41
yes
Sari Issa
20:44
So if Q sends all vectors in R^n to 0, q is both negative and positive semidefinite?
Sari Issa
21:34
Ok great
Alessio D'Andrea
23:09
false
Nicolas Mrowietz
23:11
false?
Sophia
23:16
can also be semi-
Alessio D'Andrea
23:18
It could also be semi
Tesii
26:54
no..
Tesii
29:20
yes
Tesii
29:26
thanks!
Sari Issa
31:22
Isnt a x^2 term missing?
Tesii
31:40
ahaa yes now it's clear
Tesii
31:46
thanks for the example
Aline Klaus
35:25
does this work for all symmetric matrices?
nikolaihorozov
41:17
yes
Tesii
41:20
yes
Aline Klaus
44:25
in the opposite, if i know the Eigenvalues, i can directly say the quadratic form is pos/neg/… definite? (even if i dont know the quadr. form yet)
Aline Klaus
44:41
okay thanks
nikolaihorozov
50:53
can we use eigenvalues or determinants to see whether a matrix is semi positive or negative
nikolaihorozov
51:41
ok thank you
Sari Issa
54:39
A question to the matrix S, if one of the eigenspaces has a dimension>1, do we always simply use the basis of the eigenspace rather than the eigenvector?
Sari Issa
55:12
can we use any eigenvectors in the space?
Sari Issa
55:22
in S
Sari Issa
55:57
ok thanks
Marc Foertig
56:28
Thanks very much as always :)
Nicolas Mrowietz
56:29
thanks!
Michelle
56:29
Thank you
Aline Klaus
56:32
merci
nikolaihorozov
56:32
thank you very much
Albina Kudoyarova
56:34
thanks a lot!
Alessio D'Andrea
56:39
Thanks!
rosie
56:43
you explain so good! thank you
Robert Bibaj
56:53
how many sheets are left? 2 or 3?
Tesii
57:02
thanks for your help!
j
57:10
thank you!!
Robert Bibaj
57:14
thx