Problem:
$$\int\frac{1}{2}-\frac{3}{2x+4}dx$$
Using two different methods I am getting two different answers and have trouble finding why.
Method 1:
$$\int\frac{1}{2}-\frac{3}{2x+4}dx$$
$$\int\frac{1}{2}-\frac{3}{2}\left(\frac{1}{x+2}\right)dx$$ $$\int\frac{1}{2}dx-\frac{3}{2}\int\frac{1}{x+2}dx$$ $$\frac{1}{2}x-\frac{3}{2}\int\frac{1}{x+2}dx$$ $$x+2=u$$ $$dx=du$$ $$\frac{1}{2}x-\frac{3}{2}\int\frac{1}{u}du$$
$$\frac{1}{2}x-\frac{3}{2}\ln{|x+2|}+C$$
Method 2: $$\int\frac{1}{2}-\frac{3}{2x+4}dx$$
$$\int\frac{1}{2}-3\left(\frac{1}{2x+4}\right)dx$$ $$\int\frac{1}{2}dx-3\int\frac{1}{2x+4}dx$$ $$\frac{1}{2}x-3\int\frac{1}{2x+4}dx$$ $$2x+4=u$$ $$dx=\frac{du}{2}$$ $$\frac{1}{2}x-\frac{3}{2}\int\frac{1}{u}du$$
$$\frac{1}{2}x-\frac{3}{2}\ln{|2x+4|}+C$$
Both answers are the same, mind the constant: $$\ln|2x+4|+\color{blue}{C_1}=\ln|2\left(x+2\right)|+\color{blue}{C_1}=\ln|x+2|+ \underbrace{\ln 2 + \color{blue}{C_1}}_{\color{purple}{C_2}} = \ln|x+2|+\color{purple}{C_2}$$