Question

After a certain drug is injected into a patient, the concentration C of the drug in the bloodstream is monitored. At time t(greater than)0 (in minutes since the injection), the concentration (in mg/L) is given by the equation:

C(t)=45t/t^2 +9

What is the eventual concentration of the drug? ______mg/L

Answer 1

\[\frac{45t}{t^2+9}\] ?

Answer 2

the eventual concentration? do they specify a time constraint?

Answer 3

I assume it peaks at certain point

Answer 4

given that the initial concentration is the most concentrated it can be; unless of course the body starts making more of it :)

Answer 5

time is greater than 0

Answer 6

http://www.wolframalpha.com/input/?i=lim {t+to+infinity}+45t%2Ft^2+%2B9

the limit as t goes to inifinty is either going to be 0 or 9 depending on the original format of the equation

Answer 7

http://www.wolframalpha.com/input/?i=lim {t+to+infinity}+45t%2F%28t^2+%2B9%29

Answer 8

it chopped the links .....

Answer 9

maybe this version?

http://www.wolframalpha.com/input/?i=lim(t+to+infinity)+45t%2F%28t^2+%2B9%29

Answer 10

that works, the parser doesnt like the { } brackets apparently

Answer 11

http://tinyurl.com/42ldltb

Answer 12

so based on these graphs what r we assuming the eventual concentration is in mg/L

Answer 13

I think it is asking for peak concentration

Answer 14

if the equation is: \(\cfrac{4t}{t^2}+9\) we would get 9

if the equation is: \(\cfrac{4t}{t^2+9}\) we would get 0

Answer 15

if its asking for peak concentraion than yeah, my reply would not have any bearing

Answer 16

its 45t/(t^2+9)

Answer 17

without knowing what it means by "eventual" concentration; i wouldnt be able to give a definitive answer

Answer 18

see that is my problem

Answer 19

i assume it means as time reaches into eternity .... and ive been known to be wrong :)

Answer 20

if its asking when the concentration reaches a peak value; it would be at t=3, at a value of 15/2 .....

Answer 21

and or 7.5?