Trig Func Plot Error and Trig Solving Error

[FrankP]

Quote:[1] Why is there a asymptote for some graph and not for others?

Well, even the internal representation of the relation

Y=1/(X-1)+2/(X-1)

in the Advanced Graph App on my Android Emu decides to draw a vertical line on the definition gap X=1. But no line at X=1 for

Y=1/(X-1)+1/(X-1)

!?? Strange.
But maybe an acceptable workaround could be drawing the result of the CAS command collect of the function? So in your case:

collect(cot(x)^2+3*csc(x))

The result

(1+3*sin(X)-sin(X)^2)/sin(X)^2

has no assymtote anymore.