To solve the integral \(\int \cos^2(x) \sin(x) \, dx\), we can use a substitution method. Let \( u = \cos(x) \), then \( du = -\sin(x) \, dx \). This substitution simplifies the integral to a form that is easier to integrate.
Para resolver la integral \(\int \cos^2(x) \sin(x) \, dx\), realizamos la sustitución \(u = \cos(x)\). Entonces, \(du = -\sin(x) \, dx\), lo que implica que \(-du = \sin(x) \, dx\). Esto transforma la integral en:
\[
\int \cos^2(x) \sin(x) \, dx = -\int u^2 \, du
\]
Ahora, integramos \(-\int u^2 \, du\):
\[
-\int u^2 \, du = -\frac{u^3}{3} + C
\]
Sustituyendo de nuevo \(u = \cos(x)\), obtenemos:
\[
-\frac{\cos^3(x)}{3} + C
\]
La solución de la integral es:
\[
\boxed{-\frac{\cos^3(x)}{3} + C}
\]