Answer:
At light intensity I = 3, is P a maximum
Step-by-step explanation:
Given:

now differentiating the above equation with respect to Intensity 'I' we get

or

or

or

Now for the maxima

thus,

or

or

or

or
I = 3
thus, for the value of intensity I = 3, the P is maximum
at I = 3

or

or
