Answer
$$\int\frac{1}{\sqrt{5s+4}}ds=\frac{2\sqrt{5s+4}}{5}+C$$
Work Step by Step
$$A=\int\frac{1}{\sqrt{5s+4}}ds$$
We set $u=\sqrt{5s+4}$.
Then $$du=\frac{(5s+4)'}{2\sqrt{5s+4}}ds=\frac{5}{2\sqrt{5s+4}}ds$$
That means, $$\frac{1}{\sqrt{5s+4}}ds=\frac{2}{5}du$$
Therefore, $$A=\frac{2}{5}\int du=\frac{2u}{5}+C$$ $$A=\frac{2\sqrt{5s+4}}{5}+C$$
