Recent content by Alex6200

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    Linear Algebra Basics: Finding a Basis for Subspaces in R3"

    Oh, so when he says "Find a basis", he doesn't mean find all of the bases, he just means find a single vector in the basis? So if I had another question "Find a basis for a subspace of R3 in which all vectors satisfy: (1 1 0) v = 0 Then I could just give a vector like: (-1, 1, 0)...
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    Linear Algebra Basics: Finding a Basis for Subspaces in R3"

    Hi, I had a basic linear algebra question Question #1 Homework Statement Find a basis for the subspace of R3 for which the components in all of the vectors sum to zero. Homework Equations If u and v are in w and w is a subspace, then a*u + b*v is in w. The Attempt at a...
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    Yeah. This is like my 2nd or 3rd proof so admittedly I'm a little rusty on how to formally write out the proofs.
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    Okay, here's how I approached the problem. u is in S \cap T v is in S \cap T a, b are scalars If S \cap T is a subspace, then au + bv is in S \cap T. If au + bv is in S \cap T, then au + bv is in both S and T. au + bv is in S because S is a subspace and au + bv is in T because...
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    Thanks. Can I ask if I did another question correctly? The question asks: Show that if S and T are subspaces of a vector space V, then S \cap T is also a subspace. My Solution thus far S \cap T \subset S and S is a subspace, so S \cap T is also a subspace. That almost...
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    The way I did it was: W = {(f in C[0, 1]): f(1/2) = 0} f(x) and g(x) are in the subset W if W is a subspace then h(1/2) = 0 for h(x) = a*f(x) + b*g(x) h(1/2) = a*f(1/2) + b*g(1/2) h(1/2) = a*0 + b*0 h(1/2) = 0 So W is a subspace. -- Does that seem about right?
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    I definitely understand the logic of what you're saying. If f(1/2) and g(1/2) are both 0, then (f + g)(1/2) will also be zero. But I don't know how to say it formally.
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    Is the subset of C([0,1]) with f(1/2) = 0 a subspace?

    Subspace of a Function?!? Homework Statement {f \in C([0, 1]): f(1/2) = 0} Is this subset of C([0,1]) a subspace? Homework Equations C[0,1] be the set of all functions that are continuous on [0, 1]. (f + g)(x) = f(x) + g(x) (af)(x) = a*f(x) The Attempt at a Solution...
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    Does everyone here have an inferiority complex?

    Yes, but I think my point still stands that it's hard for applicants to know how much being a star athlete, minority, or born into a low socioeconomic class matters in the admissions process - so we shouldn't be surprised that tons of kids apply to schools where they aren't competitive. In...
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    Taking the derivative of a definite integral

    Well, the actual problem I want to solve is: F(s) = \int_{0}^{\infty} e^{-st}f(t) dt for f(t). Now I want to take the derivative of both sides, and then multiply by e^{-st}, and then get f(t). Now I know from looking at Laplace transforms that the infinity part always evaluates to...
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    Taking the derivative of a definite integral

    How do I do it? For example, if I have: \int_{0}^{\infty}sf(x) dx How do I take the derivative with respect to x? I was trying to derive the formula for an inverse laplace transform when I realized that I didn't know how to take the derivative of a definite integral.
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    Does everyone here have an inferiority complex?

    Yes, but how do kids For example, I got rejected at my first and third choices, and waitlisted at my second choice. For all 3 schools I was within the middle 50th percentiles for SATs and below average for grades. How was I supposed to know if my ECs would be good enough to overcome my grades?
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    Does everyone here have an inferiority complex?

    But the situation sort of confuses applicants because these schools DO accept students with some SAT sections below 700, and it's hard for applicants to know if their "soft" factors compensate for below average test scores, since they don't know what admissions are like.
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    How Much of Physics Relies on Mathematics?

    Hmmm... Joking aside, I'm curious if anyone has a correlation between physics grades and math grades? Or physics SAT subject test and Math SAT subject test.
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    How Much of Physics Relies on Mathematics?

    He might be asking for a coefficient of correlation between mathematics ability and physics scores. That would tell him how much of being a successful physicist overlaps with mathematics. Perhaps the collegeboard publishes a statistic like that?
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