Integral dari $$$x^{\frac{3}{2}} \ln\left(x\right)$$$

Temukan $$$\int x^{\frac{3}{2}} \ln\left(x\right)\, dx$$$.

Untuk integral $$$\int{x^{\frac{3}{2}} \ln{\left(x \right)} d x}$$$, gunakan integrasi parsial $$$\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}$$$.

Misalkan $$$\operatorname{u}=\ln{\left(x \right)}$$$ dan $$$\operatorname{dv}=x^{\frac{3}{2}} dx$$$.

Maka $$$\operatorname{du}=\left(\ln{\left(x \right)}\right)^{\prime }dx=\frac{dx}{x}$$$ (langkah-langkah dapat dilihat di ») dan $$$\operatorname{v}=\int{x^{\frac{3}{2}} d x}=\frac{2 x^{\frac{5}{2}}}{5}$$$ (langkah-langkah dapat dilihat di »).

Jadi,

$${\color{red}{\int{x^{\frac{3}{2}} \ln{\left(x \right)} d x}}}={\color{red}{\left(\ln{\left(x \right)} \cdot \frac{2 x^{\frac{5}{2}}}{5}-\int{\frac{2 x^{\frac{5}{2}}}{5} \cdot \frac{1}{x} d x}\right)}}={\color{red}{\left(\frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - \int{\frac{2 x^{\frac{3}{2}}}{5} d x}\right)}}$$

Terapkan aturan pengali konstanta $$$\int c f{\left(x \right)}\, dx = c \int f{\left(x \right)}\, dx$$$ dengan $$$c=\frac{2}{5}$$$ dan $$$f{\left(x \right)} = x^{\frac{3}{2}}$$$:

$$\frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - {\color{red}{\int{\frac{2 x^{\frac{3}{2}}}{5} d x}}} = \frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - {\color{red}{\left(\frac{2 \int{x^{\frac{3}{2}} d x}}{5}\right)}}$$

Terapkan aturan pangkat $$$\int x^{n}\, dx = \frac{x^{n + 1}}{n + 1}$$$ $$$\left(n \neq -1 \right)$$$ dengan $$$n=\frac{3}{2}$$$:

$$\frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - \frac{2 {\color{red}{\int{x^{\frac{3}{2}} d x}}}}{5}=\frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - \frac{2 {\color{red}{\frac{x^{1 + \frac{3}{2}}}{1 + \frac{3}{2}}}}}{5}=\frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - \frac{2 {\color{red}{\left(\frac{2 x^{\frac{5}{2}}}{5}\right)}}}{5}$$

Oleh karena itu,

$$\int{x^{\frac{3}{2}} \ln{\left(x \right)} d x} = \frac{2 x^{\frac{5}{2}} \ln{\left(x \right)}}{5} - \frac{4 x^{\frac{5}{2}}}{25}$$

Sederhanakan:

$$\int{x^{\frac{3}{2}} \ln{\left(x \right)} d x} = \frac{2 x^{\frac{5}{2}} \left(5 \ln{\left(x \right)} - 2\right)}{25}$$

Tambahkan konstanta integrasi:

$$\int{x^{\frac{3}{2}} \ln{\left(x \right)} d x} = \frac{2 x^{\frac{5}{2}} \left(5 \ln{\left(x \right)} - 2\right)}{25}+C$$

$$$\int x^{\frac{3}{2}} \ln\left(x\right)\, dx = \frac{2 x^{\frac{5}{2}} \left(5 \ln\left(x\right) - 2\right)}{25} + C$$$A