\(Tacó\)
\(4n-3⋮n+1\Rightarrow4\left(n+1\right)⋮n+1\Rightarrow4n+4⋮n+1\)
\(\Rightarrow4n+4-\left(4n-3\right)⋮n+1\Rightarrow7⋮n+1\Rightarrow n+1\in\left\{\pm1;\pm7\right\}\)
\(\Rightarrow n\in\left\{-2;0;6;-8\right\}\)
b, \(K=\frac{2}{3+4n}\)
\(\Rightarrow GTLN\left(K\right)\Leftrightarrow n=0\Rightarrow\frac{2}{3+4n}=\frac{2}{3}\Rightarrow GTLN\left(K\right)=\frac{2}{3}\)