Answer:
a) The rate of change of the brightness after t days is [tex]B^{\prime}(t) = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
b) The rate of increase after one day is of 0.0915.
Step-by-step explanation:
The brightness after t days is given by:
[tex]B(t) = 4.2 + 0.45\sin{(\frac{2\pi t}{4.4})} = 4.2 + 0.45\sin{(0.4545\pi t)}[/tex]
A) Find the rate of change of the brightness after t days.
This is [tex]B^{\prime}(t)[/tex]
The derivative of a constant is 0, the derivative of [tex]\sin{at}[/tex] is [tex]a\cos{at}[/tex]
So, in this case, we have that:
[tex]B^{\prime}(t) = 0.45*0.4545\pi\cos{(0.4545\pi t)} = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
The rate of change of the brightness after t days is [tex]B^{\prime}(t) = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
B) Find the rate of increase after one day.
This is [tex]B^{\prime}(1)[/tex]. So
[tex]B^{\prime}(1) = 0.204525\pi\cos{(0.4545\pi)} = 0.0915[/tex]
The rate of increase after one day is of 0.0915.
