Question Number 131445 by rs4089 last updated on 04/Feb/21
![](https://www.tinkutara.com/question/18510.png)
Answered by mathmax by abdo last updated on 04/Feb/21
![∣(x+y)sin((1/(x+y)))∣≤∣x+y∣ ⇒lim_((x,y)→(0,0)) (x+y)sin((1/(x+y)))=0](https://www.tinkutara.com/question/Q131447.png)
$$\mid\left(\mathrm{x}+\mathrm{y}\right)\mathrm{sin}\left(\frac{\mathrm{1}}{\mathrm{x}+\mathrm{y}}\right)\mid\leqslant\mid\mathrm{x}+\mathrm{y}\mid\:\Rightarrow\mathrm{lim}_{\left(\mathrm{x},\mathrm{y}\right)\rightarrow\left(\mathrm{0},\mathrm{0}\right)} \:\:\left(\mathrm{x}+\mathrm{y}\right)\mathrm{sin}\left(\frac{\mathrm{1}}{\mathrm{x}+\mathrm{y}}\right)=\mathrm{0} \\ $$