Let $X$ be Banach space. True or false:
$X$ is non-separable if and only if there exist at least $2^c$ many complemented subspace in $X$.
Def. A closed subspace $V$ is complemented if there exists a closed subspace $W$ with $X=V\oplus W$?
2026-03-26 11:16:21.1774523781
Complemented sub-spaces in a non-separable space.
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