I have been trying this problem for hours. I can't believe I can't get it. The question is "Find a subset U of R^2 such that U is closed under scalar multiplication but is not a subspace of R^2". I know that for U to be a subspace 0 must be an element of U and U has to be closed under scalar multiplication and vector addition. If U is closed under scalar multiplication then it must contain O vector right? So I have to think of a subset that is not closed under addition, but is closed under multiplication right? I can not think of any. Does anyone have an idea of one that satifies these properties?(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Help with subspace

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