\"\"

\

The substitution is

\

The expression for velocity of falling object is \"\".

\

Differentiate on each side with respect to \"\"..

\

\"\"

\

\"\".

\

Logistic differential equation is \"\".

\

Thus, \"\"

\

\"\"

\

Replace \"\" in the expression. \ \

\

\"\"

\

\"\".

\

\"\"

\

(b)

\

Consider \"\".

\

Solution for the linear differential equation \"\" is \"\".

\

\"\"

\

\"\"

\

\"\".

\

From 9.4.7 \"\".

\

Compare the both equations, here \"\".

\

\"\"

\

(a) \"\" .

\

(b) \"\".