The Logistic Equation · Calculus
philschatz.com › calculus-book › contentsThe solution to the logistic differential equation has a point of inflection. To find this point, set the second derivative equal to zero: P ( t ) = P 0 K e r t ( K − P 0 ) + P 0 e r t P ′ ( t ) = r P 0 K ( K − P 0 ) e r t ( ( K − P 0 ) + P 0 e r t ) 2 P ″ ( t ) = r 2 P 0 K ( K − P 0 ) 2 e r t − r 2 P 0 2 K ( K − P 0 ) e 2 r t ( ( K − P 0 ) + P 0 e r t ) 3 = r 2 P 0 K ( K − P 0 ) e r t ( ( K − P 0 ) − P 0 e r t ) ( ( K − P 0 ) + P 0 e r t ) 3 .
The Logistic Differential Equation
mathserver.neu.edu › ~gilmore › U343su05filesThis is the Logistic Differential Equation. We will now solve this equation. We separate the variables in the equation: † dP dt = kP(M-P) to obtain † dP P(M-P) = kdt Use partial fractions on the LHS to get: † dP P(M-P) = 1 m P + 1 m M-P Ê Ë Á Á Á ˆ ¯ ˜ ˜ ˜ dP Integrating both sides of the equation now yields † 1 M lnP - 1 m ln(M-P) = kt + c or, † ln P M-P Ê Ë Á ˆ ¯