$\"\"$

The rate of change of $\"\"$ with respect to $\"\"$ is proportional to $\"\"$ .

The differential equation is $\"\"$ .

$\"\"$

Integrate on both sides.

$\"\"$ \ \

$\"\"$

Therefore, the general solution of $\"\"$ is $\"\"$ .

$\"\"$

The general solution is given by $\"\"$ is $\"\"$ .