Why the function sequence does not converge uniformly

61 Views Asked by At

$f_n : \Bbb R → \Bbb R$ : $f_n (x) = \frac{nx}{1+|nx|}$

a) To show that the function sequences f are continuous for all n ∈ ℕ.

b) Determine the limit function

c) Why the function sequence does not converge uniformly

My proposed solution:

a) Since for all n $f_n$ is the quotient of 2 continuous functions and the denominator never becomes 0, fn is continuous for all n, actually this is the easiest part.

b) I calculated the limit and got 1 for x>0 and -1 for x<o.

c) Can we say that because f(x) from part b) is not continuous --> fn is not uniformly convergent ?

1

There are 1 best solutions below

0
On BEST ANSWER

a) $f_n$ is continuous for all $n\in\mathbb{N}$ because it is the quotient of continuous functions whose the denominator is always positive

The answer you gave in b) it is correct and so it is the answer to c). If $f_n$ converged uniformily then the limit function would need to be continuous. More info