Assume a function f is dependent on measurable quantities x
     Assume a function f is dependent on measurable quantities x. y. and z. Show a walid uncertainty expression for f using propagation of errors with standard deviations for the function if  f = x^2-y^2/z  A single deadly virus multiplies exponentially. From the plot below find a valid expression for the population N(t) of the virus If the virus is lethal when the population reaches 50.000, how long do you have to live?   
  
  Solution
a.the curve is, y=5x
and y=Ln(N)
Ln(N)=5x
so. N=Exp[5x]
N(t)=Exp[5x(t)]
N(t)=Exp[5t] as x=t
b. Now N(t)=50,000
So, 50,000=Exp[5t]
5t=Ln(50,000)
t=Ln(50,000)/5 hour=10.82 hour

