\(\lim\limits_{x\rightarrow\infty}\frac{\left(x-1\right)^2\left(7x+2\right)^2}{\left(2x+1\right)^4}=\lim\limits_{x\rightarrow\infty}\frac{x^2\left(1-\frac{1}{x}\right)^2.x^2\left(7+\frac{2}{x}\right)^2}{x^4\left(2+\frac{1}{x}\right)^4}=\frac{1.7^2}{2^4}=\frac{49}{16}\)