\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i35)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
'diff(y, x) = (y*(x*cos(x)-y-sin(x)))/(x\^{}2 + y*x);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o35}
\frac{d}{d x} y=\frac{\left( -y-\sin{(x)}+x \cos{(x)}\right)  y}{x y+{{x}^{2}}}\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i27)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
f0(x, y):= y = sin(x)-x*log(y);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o27}
\operatorname{f0}\left( x,y\right) :=y=\sin{(x)}-x \log{(y)}\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i28)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
f0(pi/2, 1);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o28}
1=\sin{\left( \frac{pi}{2}\right) }\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i40)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
d: diff(f0(x, y));


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{d}
\operatorname{del}(y)=\left( \cos{(x)}-\log{(y)}\right)  \operatorname{del}(x)-\frac{x \operatorname{del}(y)}{y}\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i43)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
solve(d, del(y))/del(x);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o43}
[\frac{\operatorname{del}(y)}{\operatorname{del}(x)}=-\frac{y \log{(y)}-\cos{(x)} y}{y+x}]\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i31)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
f(yp):= yp = (y*(x*cos(x)-y-sin(x)))/(x\^{}2 + y*x);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o31}
\operatorname{f}\left( \mathit{yp}\right) :=\mathit{yp}=\frac{y\, \left( x \cos{(x)}-y-\sin{(x)}\right) }{{{x}^{2}}+y x}\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i32)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
f(-(y*log(y)-cos(x)*y)/(y+x));


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o32}
\frac{\cos{(x)} y-y \log{(y)}}{y+x}=\frac{\left( -y-\sin{(x)}+x \cos{(x)}\right)  y}{x y+{{x}^{2}}}\mbox{}
\]
%%%%%%%%%%%%%%%

\noindent
%%%%%%%%%%%%%%%
%%% INPUT:
\begin{minipage}[t]{4em}\color{red}\bf
(\% i33)
\end{minipage}
\begin{minipage}[t]{\textwidth}\color{blue}
log(y)=y+sin(x);


\end{minipage}
%%% OUTPUT:
\[\displaystyle \tag{\% o33}
\log{(y)}=y+\sin{(x)}\mbox{}
\]
%%%%%%%%%%%%%%%