Câu hỏi 6

Ta có: \(I=\underset{x\to {{\left( -1 \right)}^{-}}}{\mathop{\lim }}\,\frac{2-x}{x+1}\)

Ta thấy \(\underset{x\to {{\left( -1 \right)}^{-}}}{\mathop{\lim }}\,\left( 2-x \right)=3>0,\,\,\underset{x\to {{\left( -1 \right)}^{-}}}{\mathop{\lim }}\,\left( x+1 \right)=0,\,\,x\to {{\left( -1 \right)}^{-}}\Rightarrow x<-1\Leftrightarrow x+1<0\Rightarrow I=-\infty \)

Chọn C.