|
|
b $ \mathop {\lim }\limits_{x \to -\infty }\frac{(3-2x)^3(1-3x^2)}{7x^5-8x^2+3}$
$ =\mathop {\lim }\limits_{x \to -\infty }\frac{\dfrac{(3-2x)^3}{x^3}.\dfrac{(1-3x^2)}{x^2}}{\dfrac{7x^5-8x^2+3}{x^5}}$
$ =\mathop {\lim }\limits_{x \to -\infty }\frac{\left ( \dfrac{3}{x}-2 \right )^3.\left ( \dfrac{1}{x^2}-3 \right )^2}{7-\dfrac{8}{x^3}+\dfrac{3}{x^5}}$
$=\dfrac{(-2)^3.(-3)^2}{7}$
|