Recent content by sampahmel

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    ODE with trigonometric functions of solutions

    Thanks a lot guys. I think I got it after googling the Jacobian suggested by hunt_mat. I will derive wrt to each variable and evaluate at the point I am trying to linearize. Then I can finally use the matrix product that I am familiar with. Thanks.
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    ODE with trigonometric functions of solutions

    Higher Calculus. By the way, do I take logs to linearize it?
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    ODE with trigonometric functions of solutions

    This is something new that I have never come across. How can I go about to linearize it?
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    ODE with trigonometric functions of solutions

    Exactly. Thank you. This, I know how to solve. But the example I have given where there are sin x(t) and x(t)^2, I don't. Can anyone please enlighten me? \left( \begin{array}{c} x'(t) \\ y'(t) \end{array}\right) =\left( \begin{array}{cc} cos {x(t)} + sin {x(t)} + {x(t)}^2 + {x(t)}^2{y(t)}^3 \\...
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    ODE with trigonometric functions of solutions

    I don't understand how do you "fixed a point". And the sin and cos, calculate them using what?
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    ODE with trigonometric functions of solutions

    Or otherwise how do you know how to draw the local behavior as I usually find the eigenvalues and eigenvector to draw phase portrait. But in this case I don't know how to convert them into matrix form.
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    ODE with trigonometric functions of solutions

    My matrix product refers to: \left[x\acute{}(t) y\acute{}(t)\right] = \left[1 2 3 4\right] \left[x(t) y(t)\right] I don't know how to write the matrix in two rows, so the x and x derivative are on the 1st row in their respective matrix, while y and y derivative are on the 2nd row. {1,2}...
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    ODE with trigonometric functions of solutions

    Dear all, Homework Statement Draw behavior around (0,0) of solutions to the following nonlinear system \left( \begin{array}{c} x'(t) \\ y'(t) \end{array}\right) =\left( \begin{array}{cc} cos {x(t)} + sin {x(t)} + {x(t)}^2 + {x(t)}^2{y(t)}^3 \\ -x(t) + {y(t)}^2 + y(t) + sin {y(t)}...
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    Dynamic Programming Related Questions

    Does that mean the maximum is (1-G) where G is the smallest real >0
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    Dynamic Programming Related Questions

    Hi all, (1.) Can someone tell me the difference between a compact valued and single valued correspondence? (2.) I have been seeing repeating themes of "continuity on a compact set". Does that imply boundedness and thus possible to attain maximum? (3.) What's the difference between...
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    Using Closed/Open Balls in Rosenlicht's Intro to Analysis Proofs

    Homework Statement In Rosenlicht's Intro to Analysis, there is a proposition (p. 52). A Cauchy sequence of points in a metric space is bounded. Proof: For if the sequence is P1, P2, P3, ... and ε is any positive number and N an integer such tat d(Pn, Pm) < ε if n, m > N, then for any...
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    Open and closed sets of metric space

    But I know that in any metric space, an open ball is an open set/ closed ball is a close set. Also, the complement of an open set is a closed set. But then according to you, The complement of an open ball is not closed ball. So an open set is not an open ball?
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    Open and closed sets of metric space

    Homework Statement I am using Rosenlicht's Intro to Analysis to self-study. 1.) I learn that the complements of an open ball is a closed ball. And... 2.) Some subsets of metric space are neither open nor closed. Homework Equations Is something amiss here? I do not understand how...
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    What is the distribution density function for a normal random variable?

    I am confused with my homework problem in which it asked "If the random variable is normal, specify its distribution". What does it want? sampahmel
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    Conditional Probability and Bayes' Formula Questions

    Can anyone please answer to the above question?
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