Question
Evaluate the following limit:
$\lim\limits_{\text{x}\rightarrow1}\frac{{\text{x}-1}}{\sqrt{\text{x}^2+3}-2}$

Answer

 $\lim\limits_{\text{x}\rightarrow1}\frac{{\text{x}-1}}{\sqrt{\text{x}^2+3}-2}$

$=\lim\limits_{\text{x}\rightarrow1}\frac{(\text{x}-1)\times\big(\sqrt{\text{x}^2+3}+2\big)}{\big(\sqrt{\text{x}^2+3}-2\big)\big(\sqrt{\text{x}^2+3}+2\big)}$

$=\lim\limits_{\text{x}\rightarrow1}\frac{(\text{x}-1)\big(\sqrt{\text{x}^2+3}+2\big)}{\big({\text{x}^2+3}-4\big)}$

$=\lim\limits_{\text{x}\rightarrow1}\frac{(\text{x}-1)\big(\sqrt{\text{x}^2+3}+2\big)}{\big({\text{x}^2-1}\big)}$

$=\lim\limits_{\text{x}\rightarrow1}\frac{\sqrt{\text{x}^2+3}+2}{{\text{x}}+1}$

Putting the value x = 1

$\Rightarrow\frac{\sqrt{1+3}+2}{1+1}$

$=\frac{2+2}{2}$

$=\frac{4}{2}=2$ 

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