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{\bf Quiz 5}
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Name:
Let $U, V, W$ be vector spaces. Let $S:U\to V$ and $T:V\to W$ be linear
transformations.
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Prove that $N(S)\subseteq N(T\circ S)$.
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\item
Give an example where $N(S)\neq N(T\circ S)$.
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Suppose $T$ is injective. Prove that $N(S)=N(T\circ S)$.
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