Cho hàm số \(y=\dfrac{x-2}{x+3}\). Tìm \(y".\)
\(\dfrac{10}{\left(x+3\right)^2}\).\(\dfrac{-10}{\left(x+3\right)^2}\).\(\dfrac{5}{\left(x+3\right)^2}\).\(\dfrac{-5}{\left(x+3\right)^2}\).Hướng dẫn giải:\(y=\dfrac{x-2}{x+3}=1-\dfrac{5}{x+3}=1-5.\left(x+3\right)^{-1}\Rightarrow y'=-5.\left(-1\right)\left(x+3\right)^{-2}\Rightarrow y"=-5.\left(-1\right)\left(-2\right)\left(x+3\right)^{-3}=\dfrac{-10}{\left(x+3\right)^2}\)