Recent content by bbelson01

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    MHB Interpreting U={A|A^2=A, A is in M22}: Not a Subspace of M22

    More vector subspaces How do I interpret the following: U={A|A^2=A, A is an element of M22} is not a subspace of M22. I don't quite understand what it's asking in terms of A^2=A. Thanks. That is all the information in the question. I can't make the jump from vectors to matrices in terms of...
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    MHB Proving Vector Subspace $U \notin R^3$

    Thank you for your response. That was pretty obvious wasn't it? Ooops.
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    MHB Interpreting U={A|A^2=A, A is in M22}: Not a Subspace of M22

    How do I interpret the following: U={A|A^2=A, A is an element of M22} is not a subspace of M22. I don't quite understand what it's asking in terms of A^2=A. Thanks.
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    MHB Proving Vector Subspace $U \notin R^3$

    Hi All, How do I prove that $U=\{(x,y,z)|x \mbox{ is an integer}\}$ is not a subspace of $R^3$? I understand that I have to show $U$ is closed or not closed under vector addition and scalar multiplication but I'm unsure how I represent $x$ as an integer. I would say: let $V=\{v=(x,y,z) \in...
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    MHB Why does the equation of the level surface not have ln?

    Thanks for replying Selena. Could you please step me through how you go from ln(x^2−y+z^2) to x^2−y+z^2=0? How can you just eliminate ln? Thanks, bbelson01
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    MHB Why does the equation of the level surface not have ln?

    Could someone please help me with the following question: Consider the function g(x,y,z)=ln(x^2−y+z^2). Find an equation of the level surface of the function through the point (−1,2,1) which does not have ln. First find g(−1,2,1). When I sub in the points I get...