= Lambda-injective normed space
{title2=$\|\widetilde T\|\le\lambda\|T\|$}
For $\lambda\ge1$, a <normed vector space> $X$ is lambda-injective when every <bounded linear operator> from a subspace $Y$ of any normed space $Z$ into $X$ extends to $Z$ with the displayed norm bound. The space of <bounded scalar functions on an index set> is 1-injective: extend each coordinate functional by the <Hahn-Banach theorem> and reassemble it using the <coordinate functional representation of an operator into bounded indexed functions>.
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