Câu 1:=lim=\mathop {\lim }\limits_{x \to 0} {\frac{1}{{5x+1}^\frac{4}{5}}}=\frac{1}{({5.0+1})^\frac{4}{5}}=1
Câu 1:=\mathop {\lim }\limits_{x \to 0} (\frac{(5x+1)^\frac{1}{5}-1}{x}$=\mathop {\lim }\limits_{x \to 0} {\frac{1}{({5x+1})^\frac{4}{5}}}$$=\frac{1}{({5.0+1})^\frac{4}{5}}=1$