SOLUTION: Hello, I could use some help on this problem: A circle is shrinking in size, and the radius is given by the function r(t) = 1/(2 + t^2), where t is the time in minutes. Expre

Algebra ->  Circles -> SOLUTION: Hello, I could use some help on this problem: A circle is shrinking in size, and the radius is given by the function r(t) = 1/(2 + t^2), where t is the time in minutes. Expre      Log On


   



Question 45767: Hello,
I could use some help on this problem:
A circle is shrinking in size, and the radius is given by the function r(t) = 1/(2 + t^2), where t is the time in minutes. Express the area of the circle as a function of t, and find its value when t=4 min.
After I solve the above function, do I then have to find the area by solving area=pie(r^2)?
Thanks again,
Louis

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A circle is shrinking in size, and the radius is given by the function r(t) = 1/(2 + t^2), where t is the time in minutes. Express the area of the circle as a function of t, and find its value when t=4 min.
After I solve the above function, do I then have to find the area by solving area=pie(r^2)?
You don't have to solve the function; it is already solved for "r".
Just put the r value into the formula A=(pi)r^2
Cheers,
Stan H.