$\"\"$

The population function of $\"\"$ bacteria growing in number is $\"\"$ .

$\"\"$ .

Apply derivative on each side with respect to $\"\"$ .

$\"\"$

Rate of change of population is $\"\"$ .

$\"\"$

Rate of change of population at $\"\"$ .

$\"\"$

Substitute $\"\"$ in the above equation.

$\"\"$

$\"\"$ bacteria / hour.

$\"\"$

Rate of change of population at $\"\"$ is $\"\"$ bacteria / hour.