Funktion $$$e^{\sin{\left(x \right)}} \cos{\left(x \right)}$$$ integraali

Määritä $$$\int e^{\sin{\left(x \right)}} \cos{\left(x \right)}\, dx$$$.

Olkoon $$$u=\sin{\left(x \right)}$$$.

Tällöin $$$du=\left(\sin{\left(x \right)}\right)^{\prime }dx = \cos{\left(x \right)} dx$$$ (vaiheet ovat nähtävissä ») ja saamme, että $$$\cos{\left(x \right)} dx = du$$$.

Siis,

$${\color{red}{\int{e^{\sin{\left(x \right)}} \cos{\left(x \right)} d x}}} = {\color{red}{\int{e^{u} d u}}}$$

Eksponenttifunktion integraali on $$$\int{e^{u} d u} = e^{u}$$$:

$${\color{red}{\int{e^{u} d u}}} = {\color{red}{e^{u}}}$$

Muista, että $$$u=\sin{\left(x \right)}$$$:

$$e^{{\color{red}{u}}} = e^{{\color{red}{\sin{\left(x \right)}}}}$$

Näin ollen,

$$\int{e^{\sin{\left(x \right)}} \cos{\left(x \right)} d x} = e^{\sin{\left(x \right)}}$$

Lisää integrointivakio:

$$\int{e^{\sin{\left(x \right)}} \cos{\left(x \right)} d x} = e^{\sin{\left(x \right)}}+C$$

$$$\int e^{\sin{\left(x \right)}} \cos{\left(x \right)}\, dx = e^{\sin{\left(x \right)}} + C$$$A