Evaluate 12x+122x2+4x+10dx\displaystyle \int\frac{{{12}{x}+{12}}}{{{2}{x}^{{2}}+{4}{x}+{10}}}{\left.{d}{x}\right.} where 2x2+4x+10>0\displaystyle {2}{x}^{{2}}+{4}{x}+{10}>{0}.
First substitute u =  
Then 12x+122x2+4x+10dx=\displaystyle \int\frac{{{12}{x}+{12}}}{{{2}{x}^{{2}}+{4}{x}+{10}}}{\left.{d}{x}\right.}=\int   du
Now integrate with respect to u to get   + C
So 12x+122x2+4x+10dx\displaystyle \int\frac{{{12}{x}+{12}}}{{{2}{x}^{{2}}+{4}{x}+{10}}}{\left.{d}{x}\right.} =   + C