Suppose $A$ is a unital Banach algebra, and $x\in A$ s.t. $||x||\geq 1$, is it possible that $1-x$ invertible
2026-04-25 03:42:00.1777088520
Is $1-x$ invertible in Banach algebra
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For sure $2$ is such that $\Vert 2 \Vert =2 \ge 1$ and $1-2=-1$ is invertible.