2

I am given a function as is mentioned in title. I want to prove it uniformly continuous or discontinuous. But I am not able to do it. Any help would be appreciated.

pisco
  • 18,983
s.singh
  • 108

1 Answers1

6

Let $$x_n = 2n^2\pi + \frac{1}{n} \quad \quad y_n = 2n^2\pi$$ Then with $f(x) = \sqrt{x}\sin x$, we have $$|f(x_n)-f(y_n)| = \sqrt{2n^2\pi+\frac{1}{n}}\sin\frac{1}{n}\to \sqrt{2\pi} \quad \quad \text{ as } \quad n\to\infty$$ Hence it is not uniformly continuous over $(0,\infty)$.

pisco
  • 18,983