数学模式中的错误过多吗？

Question

有人可以向我解释一下这个过度错误吗？

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\begin{question}{2.1.35.1} Let $\mathsf{V}$ be a finite-dimensional vector space and $\mathsf{T \colon V \to V}$ be linear. Suppose that 
$\mathsf{V = R(T) + N(T)}$. Then $\mathsf{V = R(T) \oplus N(T)}$.

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