Tìm nguyên F(x)của hàm số f(x) =(x + 1)(x + 2)(x + 3)?

9/30

Tìm nguyên \[F\left( x \right)\] của hàm số \[f\left( x \right)\, = \,\left( {x + 1} \right)\left( {x + 2} \right)\left( {x + 3} \right)?\]

\[F\left( x \right)\, = \,\frac{{{x^4}}}{4}\, - \,6{x^3}\, + \,\frac{{11}}{2}{x^2} - \,6x\, + \,C\].B. \[F\left( x \right)\, = \,{x^4}\, + \,6{x^3}\, + \,11{x^2} + \,6x\, + \,C\].

\[F\left( x \right)\, = \,\frac{{{x^4}}}{4}\, + 2{x^3}\, + \,\frac{{11}}{2}{x^2} + \,6x\, + \,C\].D. \[F\left( x \right)\, = \,{x^3}\, + \,6{x^2}\, + \,11{x^2} + \,6x\, + \,C\].

Giải thích

Chọn C

Ta có: \[f\left( x \right)\, = \,\left( {x + 1} \right)\left( {x + 2} \right)\left( {x + 3} \right) = \,{x^3} + \,6{x^2}\, + \,11x\, + \,6\]

\[ \Rightarrow \,\,F\left( x \right)\, = \,\int {\left( {{x^3} + \,6{x^2}\, + \,11x\, + \,6} \right)} dx\, = \,\,\frac{{{x^4}}}{4}\, + 2{x^3}\, + \,\frac{{11}}{2}{x^2} + \,6x\, + \,C\].