$$\lim\limits_{x\to\infty}x^4.sin(\frac 4x).tan^3(\frac 2x)$$
$$\lim\limits_{x\to\infty}\dfrac{sin(\frac 4x)}{\frac 1x}.\dfrac{tan^3(\frac 2x)}{\frac{1}{x^3}}$$
$$\lim\limits_{x\to\infty}4.\dfrac{sin(\frac 4x)}{\frac 4x}.2^3.\dfrac{\left(tan(\frac 2x)\right)^3}{\frac{2^3}{x^3}}$$
$$4.2^3.\lim\limits_{x\to\infty}\left[\dfrac{sin(\frac 4x)}{(\frac{4}{x})}\right].\lim\limits_{x\to\infty}\left[\dfrac{tan(\frac{2}{x})}{(\frac{2}{x})}\right]^3 =2^5$$ olur.