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bio website cse.iitb.ac.in/~aruniyer
location India
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visits member for 2 years, 9 months
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Sep
24
answered Is vector W in the span of V1,V2,V3
Sep
24
revised Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
deleted 124 characters in body
Sep
24
comment Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
We are not choosing $x = M^{-1}y$. Remember that M is non-singular, therefore, $x \to Mx$ is a bijection.
Sep
24
comment Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
I have updated the answer with a simpler approach, which avoids finding a good x.
Sep
24
revised Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
added 362 characters in body
Sep
24
comment Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
Yeap. That is what at least I have in my mind.
Sep
24
answered Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
Sep
24
comment Subordinate norm is equal to $\Vert A\Vert_M=\Vert MAM^{-1}\Vert$ for the norm $\Vert x\Vert_M=\Vert Mx\Vert$
Always start with the definition. Also, if this is a homework, do tag your question as homework.
Sep
24
comment Prove that there is no function $f:\Bbb{R}\to\Bbb{R}$ with $f(0)>0$ such that $\forall x,y\in\Bbb{R}, f(x+y)\geq f(x)+y f(f(x))$
If you put x = 0, then the LHS in the first inequality you gave should be f(0) - yf(f(0))
Sep
15
accepted Positive Semi Definite Matrix
Sep
15
comment Positive Semi Definite Matrix
True, the general matrix will also continue to be indefinite. @Omnomnomnom has given necessary and sufficiency conditions as well. Thank you so very much to both of you for your answers.
Sep
15
comment Positive Semi Definite Matrix
This is an excellent piece of information! Thank you so very much!
Sep
15
comment Positive Semi Definite Matrix
(+1) I have added some more question to the original post. Please do give it a read as well.
Sep
15
comment Positive Semi Definite Matrix
(+1) I added some more questions to the original. Please, do give it a read as well.
Sep
15
revised Positive Semi Definite Matrix
added 158 characters in body
Sep
15
asked Positive Semi Definite Matrix
Aug
29
awarded  Nice Answer
Jul
12
comment How to parameterize the maximum of a function?
@cirpis the title says degree two polynomial
Jul
12
answered How to parameterize the maximum of a function?
May
16
comment How to prove such an elementary inequality
Precisely. (Surely you meant pth root instead of pth power).