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Integrate the following:

$$\int { \cfrac { 6 }{ { x }^{ 2 }+4x+3 } } dx$$

$2\arctan { (\frac{ ( x+2 )} {3} ) } +C$

$6\arctan { (\frac{ ( x+2 )} {3} ) } +C$

$3\ln { (\frac{ ( x+1 )}{( x+3 )} ) } +C$

$3\ln { ( \frac{( x-3 )}{( x+1 )} ) } +C$