Is there a name of the rule that $ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $?Does $lVert PrVert leq lVert QrVert$ imply $U(P,f) leq U(Q,f)$?bounded measurable functionShow that there is no non-zero polynomial $P(u,v)$ in two variables with real coefficients such that $P(x, cos x) = 0$ holds for all real $x$$f(0)=0$ and $lvert,f^prime (x)rvertleq Klvert,f(x)rvert,$ imply that $fequiv 0$.Is there a name for this set?Fourier transform of $e^-lvert lambda xrvert$Smooth curve with trace $lvert x rvert$Show that $E(Y^p)=int_0^inftypx^p-1P(Ygeq x)dx$Analysis Inequality proof technique/tool$|x|$ versus $lVert xrVert$?
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Is there a name of the rule that $ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $?
Does $lVert PrVert leq lVert QrVert$ imply $U(P,f) leq U(Q,f)$?bounded measurable functionShow that there is no non-zero polynomial $P(u,v)$ in two variables with real coefficients such that $P(x, cos x) = 0$ holds for all real $x$$f(0)=0$ and $lvert,f^prime (x)rvertleq Klvert,f(x)rvert,$ imply that $fequiv 0$.Is there a name for this set?Fourier transform of $e^-lvert lambda xrvert$Smooth curve with trace $lvert x rvert$Show that $E(Y^p)=int_0^inftypx^p-1P(Ygeq x)dx$Analysis Inequality proof technique/tool$|x|$ versus $lVert xrVert$?
$begingroup$
I'm a bit new to real analysis. Today, I came across this particular equality, whcih seems obvious to me.
$$ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $$
Is there a specific name for this?
real-analysis
$endgroup$
add a comment |
$begingroup$
I'm a bit new to real analysis. Today, I came across this particular equality, whcih seems obvious to me.
$$ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $$
Is there a specific name for this?
real-analysis
$endgroup$
add a comment |
$begingroup$
I'm a bit new to real analysis. Today, I came across this particular equality, whcih seems obvious to me.
$$ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $$
Is there a specific name for this?
real-analysis
$endgroup$
I'm a bit new to real analysis. Today, I came across this particular equality, whcih seems obvious to me.
$$ lVert x + z rVert^2 + lVert x - z rVert^2 = 2 lVert x rVert^2 + 2lVert z rVert^2 $$
Is there a specific name for this?
real-analysis
real-analysis
edited 22 hours ago
Asaf Karagila♦
306k33438769
306k33438769
asked yesterday
JaPJaP
203
203
add a comment |
add a comment |
1 Answer
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$begingroup$
This is the parallelogram law of norms induced by inner products.
$endgroup$
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
add a comment |
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1 Answer
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1 Answer
1
active
oldest
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oldest
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votes
$begingroup$
This is the parallelogram law of norms induced by inner products.
$endgroup$
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
add a comment |
$begingroup$
This is the parallelogram law of norms induced by inner products.
$endgroup$
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
add a comment |
$begingroup$
This is the parallelogram law of norms induced by inner products.
$endgroup$
This is the parallelogram law of norms induced by inner products.
answered yesterday
pulpfictionalpulpfictional
1986
1986
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
add a comment |
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
$begingroup$
Thank you so much!
$endgroup$
– JaP
yesterday
add a comment |
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