Đáp án đúng:
Giải chi tiết:a) \(y = \left( {x + 1} \right)\left( {3x - 2} \right) = 3{x^2} + x - 2\)
\( \Rightarrow y' = 6x + 1\)
b) \(y = \left( {2\sqrt x + 3} \right)\left( {4\sqrt x - 5} \right) = 8x + 2\sqrt x - 15\)
\( \Rightarrow y' = 8 + \dfrac{1}{{\sqrt x }}\)
c) \(y = \left( {2{x^3} - 9{x^2} + 1} \right)\left( {9 - 2x} \right)\)
\(\begin{array}{l}y = 18{x^3} - 4{x^4} - 81{x^2} + 18{x^3} + 9 - 2x\\y = - 4{x^4} + 36{x^3} - 81{x^2} - 2x + 9\\ \Rightarrow y' = - 16{x^3} + 108{x^2} - 162x - 2\end{array}\)
d) \(y = \left( {x - 1} \right)\left( {2x - 1} \right)\left( {3x + 2} \right)\)
\(\begin{array}{l}y = \left( {2{x^2} - 3x + 1} \right)\left( {3x + 2} \right)\\y = 6{x^3} - 9{x^2} + 3x + 4{x^2} - 6x + 2\\y = 6{x^3} - 5{x^2} - 3x + 2\\ \Rightarrow y' = 18{x^2} - 10x - 3\end{array}\)
