Đáp án:
Giải thích các bước giải:
$\lim _{x\to \:1}\left(\dfrac{x\sqrt{x+3}-2}{4x^3-x^2-3x}\right)$
Liên hợp $x\sqrt{x+3}-2$
$=\lim _{x\to \:1}\left(\dfrac{\dfrac{x^3+3x^2-4}{x\sqrt{x+3}+2}}{4x^3-x^2-3x}\right)$
$=\lim _{x\to \:1}\left(\dfrac{\left(x+2\right)^2}{x\left(x\sqrt{x+3}+2\right)\left(4x+3\right)}\right)$
$=\dfrac{\left(1+2\right)^2}{1\cdot \left(1\cdot \sqrt{1+3}+2\right)\left(4\cdot \:1+3\right)}$
`=9/28`
