Integral of sinax*ln(cosax) dx
The solution
The answer (Indefinite)
[src]
/ //-cos(a*x)*log(cos(a*x)) + cos(a*x) \
| ||---------------------------------- for a != 0|
| sin(a*x)*log(cos(a*x)) dx = C + |< a |
| || |
/ \\ 0 otherwise /
$$\int \log{\left(\cos{\left(a x \right)} \right)} \sin{\left(a x \right)}\, dx = C + \begin{cases} \frac{- \log{\left(\cos{\left(a x \right)} \right)} \cos{\left(a x \right)} + \cos{\left(a x \right)}}{a} & \text{for}\: a \neq 0 \\0 & \text{otherwise} \end{cases}$$
/ 1 cos(a) cos(a)*log(cos(a))
|- - + ------ - ------------------ for And(a > -oo, a < oo, a != 0)
< a a a
|
\ 0 otherwise
$$\begin{cases} - \frac{\log{\left(\cos{\left(a \right)} \right)} \cos{\left(a \right)}}{a} + \frac{\cos{\left(a \right)}}{a} - \frac{1}{a} & \text{for}\: a > -\infty \wedge a < \infty \wedge a \neq 0 \\0 & \text{otherwise} \end{cases}$$
=
/ 1 cos(a) cos(a)*log(cos(a))
|- - + ------ - ------------------ for And(a > -oo, a < oo, a != 0)
< a a a
|
\ 0 otherwise
$$\begin{cases} - \frac{\log{\left(\cos{\left(a \right)} \right)} \cos{\left(a \right)}}{a} + \frac{\cos{\left(a \right)}}{a} - \frac{1}{a} & \text{for}\: a > -\infty \wedge a < \infty \wedge a \neq 0 \\0 & \text{otherwise} \end{cases}$$
Piecewise((-1/a + cos(a)/a - cos(a)*log(cos(a))/a, (a > -oo)∧(a < oo)∧(Ne(a, 0))), (0, True))
Use the examples entering the upper and lower limits of integration.