Đáp án:
`1, 0`
`2, 1`
`3, -1/2`
Giải thích các bước giải:
`1, lim_{x->+\infty} (\sqrt{x+1}-\sqrt{x})`
`= lim_{x->+\infty} \frac{x+1-x}{\sqrt{x+1}+\sqrt{x}}`
`= lim_{x->+\infty} \frac{1/(\sqrt{x})}{\sqrt{1+1/x}+\sqrt{1}}`
`=0`
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`2, lim_{x->0} \frac{sinx}{x}=1`
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`3, lim_{x->0} \frac{\sqrt{1-x}-1}{x}`
`= lim_{x->0}\frac{1-x-1}{x.(\sqrt{1-x}+1)}`
`= lim_{x->0}\frac{-1}{\sqrt{1-x}+1}`
`= \frac{-1}{\sqrt{1-0}+1}`
`= -1/2`
