The equation is .
Multiply each side by .
Differentiate on both sides with respective to .
The R.H.S of the equation is , because the derivative of the constant is
.
Consider the L.H.S :
Use product rule :.
Replace with
.
Apply cross multiplication.
\Now integrate on both sides.
\Therefore, .
The function is .
(1) Draw the coordinate plane.
\(2) Graph the function for several values of
.
The curves and
represents the orthogonal trajectories.
The parabolas represent the given family of curves.
\Graph :
\