Recent content by rapple

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    Real analysis with exponential functions; given f(x) = f'(x)

    This is in real analysis in the section on exponential functions. So I can't use differential equations. The only way, I suppose, is to arrive at a contradiction if c not= f(0).
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    Real analysis with exponential functions; given f(x) = f'(x)

    Homework Statement f(x)=f'(x) for all x in R S.T there exists a c in R such that f(x) = c exp(x) for all x Homework Equations The Attempt at a Solution By defining g = f/c, I was able to show that c= f(0) But i am also supposed to show that c Not equal to any other value I...
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    Sequence of discontinuous functions

    Since lim n->inf (1/n)=0, as n-> infinity, f_n(x) will be 0 for rationals as well. which means that for any epsilon>0, if n is large enough, |f(x)-0|< epsilon for rational as well?
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    Sequence of discontinuous functions

    Homework Statement Need an example of a sequence of functions that is discountinuous at every point on [0,1] but converges uniformly to a function that is continuous at every point Homework Equations The Attempt at a Solution I used the dirichlet's function as the template f_n(x)...
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    Solving L'Hospital's Rule Homework on f(x)+f'(x)=L

    How? I can see that x->infinity, e^xf(x)/e^x is of the infinity . limx->inf f(x)/infinity. Since we don't know anything about f(x) except it s continuous and differentiable on (0,infnty), can i make the conclusion that it is not= 0 hence is of the infnty/infnty form. Proceeding with that...
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    Solving L'Hospital's Rule Homework on f(x)+f'(x)=L

    Homework Statement Given f is differentiable on (0,\infty) Given lim_{x->\infty} [f(x)+f'(x)]=L S.T lim f(x)=L and lim f'(x)=0 Hint f(x)=e^{x}f(x)/e^{x} Homework Equations The Attempt at a Solution A Lim _{x->\infty} [f(x)+f'(x)]=L Then for some \epsilon>0...
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    Subgroup of D_n: Proving <f> Not Normal

    Homework Statement S.T <f> is not normal. where f is a reflection Homework Equations <f>={e,r^0 f, r^1f,r^2f,..} WTS For any g in D-n, g(r^kf)g^-1 Not In <F> The Attempt at a Solution Elements of D-n are r^k, r^kf For r^k, (r^k)(r^if)(r^-k) is in <f>. So I am stuck
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    Partial fractions pronblem help

    Ok. F'(x)=d/dx(integ f(t)) over 0 to x^2. = f(x).2x=(1/1+x^6).2x
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    Partial fractions pronblem help

    The derivative of an integral is the function itself if it is continuous over the specified region. In this case, the function is not continuous at t=-1, But that is not in 0 to x^2. I don't know how Leibniz rule works here
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    Partial fractions pronblem help

    I got the problem wrong. F(x)=Integ (1+t^3)^-1 from 0 to x^2. Find F'(x) How do I proceed
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    Partial fractions pronblem help

    I tried partial fractions but I landed up with A/(1+t) + B/(1-t+t^2). Cannot find values for A & B that work.
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    Partial fractions pronblem help

    Homework Statement F(X)=[tex]\int[/\frac{1}{1+t^3} Homework Equations The Attempt at a Solution I have tried different substitutions to find fog where g(t) = ? But am getting stuck
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    Does pv=0 Imply pv₁=pv₂=0 in Monic Polynomial Problems?

    Homework Statement Let us say that p(c) is a monic polynomial such that when applied to a particular v, we have pv=0. Let V be a finite dimensional vector space. Let V be the direct sum of k invariant subspaces. Then v = v_1+...+v_k. When I apply pv=0 does this imply that pv_1=pv_2=0...
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    Continuous function on intervals

    Thank you. You seem to have a way of making it happen!
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