How to integrate sin ln(x)


 

\[\smallint \sin lnx{\rm{d}}x\] \[\begin{array}{l} By\;Substitution\\ suppose \Rightarrow z = \ln x\\ {e^z} = x\\ dz = 1/xdx\\ \smallint {{\rm{e}}^{\rm{z}}}\sin z{\rm{d}}z\\ By\;Parts\\ Let \Rightarrow u = \sin z\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;dv = {e^z}\\ du = cosz\;\;\;\;\;\;\;\;\;\;\;\;\;v = {e^z}\\ \smallint {e^z}\sin z\;\;\;dz = {e^z} \cdot \sin z - \smallint {e^z}\cos z{\rm{d}}z\\ By\;Parts\\ Let \Rightarrow g = \cos z\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;df = {e^z}\\ dg = - sinz\;\;\;\;\;\;\;\;\;\;f = {e^z}\\ \smallint {e^{\rm{z}}}\sin {\rm{zd}}z = {e^z}\sin z - \left( {\;{e^z}\cos z + \smallint {e^z}\sin z{\rm{d}}z\;} \right)\\ \smallint {{\rm{e}}^z}\sin z{\rm{d}}z = {{\rm{e}}^z}\sin z - {{\rm{e}}^z}\cos z\\ \smallint {{\rm{e}}^z}\sin z{\rm{d}}z = \frac{1}{2}\left( {{e^z}\sin z - {e^z}\cos z} \right) \end{array}\]

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