Integral de $$$\left(x - 3\right)^{2}$$$

Encontre $$$\int \left(x - 3\right)^{2}\, dx$$$.

Seja $$$u=x - 3$$$.

Então $$$du=\left(x - 3\right)^{\prime }dx = 1 dx$$$ (veja os passos »), e obtemos $$$dx = du$$$.

Portanto,

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

Aplique a regra da potência $$$\int u^{n}\, du = \frac{u^{n + 1}}{n + 1}$$$ $$$\left(n \neq -1 \right)$$$ com $$$n=2$$$:

$${\color{red}{\int{u^{2} d u}}}={\color{red}{\frac{u^{1 + 2}}{1 + 2}}}={\color{red}{\left(\frac{u^{3}}{3}\right)}}$$

Recorde que $$$u=x - 3$$$:

$$\frac{{\color{red}{u}}^{3}}{3} = \frac{{\color{red}{\left(x - 3\right)}}^{3}}{3}$$

Portanto,

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

Adicione a constante de integração:

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

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