Question 314855
<pre><b>
{{{f(x+y)-f(x) = Tan(x+y)-Tan(x) = ""}}} 

{{{(Tan(x)+Tan(y))/(1-Tan(x)Tan(y))-Tanx= ""}}}

{{{(Tan(x)+Tan(y))/(1-Tan(x)Tan(y))-Tan(x)( 1-Tan(x)Tan(y))/((1-Tan(x)Tan(y)) ) =""}}}

{{{(Tan(x)+Tan(y))/(1-Tan(x)Tan(y))-(Tan(x)-Tan^2xTan(y))/(1-Tan(x)Tan(y)) 
}}}

{{{((Tan(x)+Tan(y))-(Tan(x)-Tan^2xTan(y)))/(1-Tan(x)Tan(y)) 
}}}

{{{(Tan(x)+Tan(y)-Tan(x)+Tan^2xTan(y))/(1-Tan(x)Tan(y)) 
}}}

{{{(cross(Tan(x))+Tan(y)-cross(Tan(x))+Tan^2xTan(y))/(1-Tan(x)Tan(y)) 
}}}

{{{(Tan(y)+Tan^2xTan(y))/(1-Tan(x)Tan(y)) 
}}}

{{{(Tan(y)(1+Tan^2x))/(1-Tan(x)Tan(y)) 
}}}

{{{(Tan(y)Sec^2x)/(1-Tan(x)Tan(y)) 
}}}

{{{(Sec^2x*Tan(y))/(1-Tan(x)Tan(y)) 
}}}

Edwin</pre>