Is it true that there is a continuous, onto map from $(0,1]$ to $\mathbb R$?

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Is it true that there is a continuous, onto map from $(0,1]$ to $\mathbb R$?

I am trying but could not approach.

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There are 3 best solutions below

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On

One example is $$ f(x) = \frac{\sin(1/x)}{x} $$

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On

Try $\frac{\sin(\frac{1}{x})}{x}$.

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$f(x) = \frac{1}{x}$ maps $(0,1]$ to $[1,+\infty)$. Can you map the latter onto $\Bbb R$ continuously? Then compose.