Tìm giới hạn \(B=\lim\limits _{x \rightarrow+\infty} \frac{\sqrt{4 x^{2}+x}+\sqrt[3]{8 x^{3}+x-1}}{\sqrt[4]{x^{4}+3}}\)

* Hướng dẫn giải

Ta có

\(B=\lim \limits_{x \rightarrow+\infty} \frac{|x| \sqrt{4+\frac{1}{x}}+x \cdot \sqrt[3]{8+\frac{1}{x^{2}}-\frac{1}{x^{3}}}}{|x| \sqrt[4]{1+\frac{3}{x^{4}}}}=\lim \limits_{x \rightarrow+\infty} \frac{\sqrt{4+\frac{1}{x}}+\sqrt[3]{8+\frac{1}{x^{2}}-\frac{1}{x^{3}}}}{\sqrt[4]{1+\frac{3}{x^{4}}}}=4\)