Can you me proving , uniform convergence implies pointwise convergence

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Uniform convergence of a sequence of functions implies pointwise convergence, as uniform convergence ensures that the same level of closeness (defined by epsilon) applies uniformly across all points in the domain. The discussion highlights that for uniform convergence, one can find a single N such that for all x, the difference between the functions and their limit is less than epsilon when n exceeds N. In contrast, pointwise convergence allows for N to vary depending on both epsilon and the specific point x. This distinction clarifies why uniform convergence guarantees pointwise convergence but not vice versa. Understanding these definitions is crucial for grasping the relationship between the two types of convergence.
shehpar
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I don't know, I started from the definition of uniform convergence and it seems pretty obvious to me , can anybody start me at least towards right direction?
 
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Yes, that pretty much all it takes.

Definition of "uniformly convergent": \{f_n(x)\} converges to f(x) as n goes to infinity uniformly if and only if, given \epsilon> 0, there exist N such that if n > N, then |f_n(x)- f(x)|< \epsilon.

Definition of "convergent": {f_n(x)} converges to f(a) for given a as n goes to infinity if and only if given \epsilon> 0, there exsit N such that if n> N, then |f_n(a)- f(a)|< \epsilon.

Basically, "uniformly convergent" requires that, given \epsilon, you be able to use the same \delta for every value of x. Just "convergent" means the value of \delta may depend upon \epsilon and the value of x at which the function is evaluated.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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