The equation is .
Diffrentiate with respective to .
Replace with
.
Consider .
Seperate the variables.
\Now integrate on both sides.
\Where is an integration constant.
.
Substiute .
.
From the logarthamic property : and
(1). Draw the coordinate plane.
\(2). Graph the function for several values of
.
The circles represents the given family of curves.
\The curves represents the orthoganal trajectories.
\Graph :
\