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  "body": "\n## Statement\n\nLet $A$ be an $n \\times n$ [[invertible matrix|0EB9N0S33C]] with inverse $B$.\nThen $B$ is also invertible, and its inverse is $A$.\nIn symbols, $(A^{-1})^{-1} = A$.\n\n## Remarks\n\nThe proof is one line.\nSince $B$ is the inverse of $A$, we have $AB = BA = I$.\nThese two equations say exactly that $A$ is an inverse of $B$.\nBy uniqueness of inverses, $A$ is the inverse of $B$.\n",
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