question
\[\int\limits \frac{\cos}{1-cosx}dx\]\[\int\limits \frac{\cos^2\frac{x}{2}-\sin^2\frac{x}{2}}{2\sin^2\frac{x}{x}}dx\]\[\frac{1}{2}[\int\limits (\cot^2\frac{x}{2}-1)dx]\]\[\frac{1}{2}[\int\limits (cosec^2\frac{x}{2}-2)dx]\]\[\frac{1}{2}\int\limits cosec^2\frac{x}{2}dx-\int\limits dx\]\[-\cot \frac{x}{2}-x+C\] OK?
@mathmath333
\(\Huge \begin{align} \color{black}{ \checkmark \hspace{.33em}\\~\\ }\end{align}\)
I was confused since the answer that was given was... \[-cosecx-cotx-x+C\] @mathmath333
Ahh, nailed it \[\frac{-1}{sinx}+\frac{-cosx}{\sin}=\frac{-1}{sinx}(1+cosx)=\frac{-2\cos^2\frac{x}{2}}{2\sin \frac{x}{2}\cos \frac{x}{2}}\]\[=-\cot \frac{x}{2}\]
\(\large \begin{align} \color{black}{ -\cot x-x \hspace{.33em}\\~\\ =-\dfrac{\cos x}{\sin x} -x \hspace{.33em}\\~\\ =-\dfrac{2\cos^2 x}{2\sin x\cos x} -x \hspace{.33em}\\~\\ =-\dfrac{2(\frac{1+\cos x}{2})}{sinx} -x \hspace{.33em}\\~\\ =-\dfrac{1+\cos x}{sinx} -x \hspace{.33em}\\~\\ =-cosec ~ x-\cot x -x \hspace{.33em}\\~\\ }\end{align}\)
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