Let be a function satisfying and . Compute .
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
Althought this differential equation is a particular case of Bernouilli differential equation I'm going to use the variable separated method what is not absolutely formal but it works. d x d y = 8 y − 2 y 2 , y ( 2 0 1 6 ) = 1 8 y − 2 y 2 d y = d x ⇒ ∫ 8 y − 2 y 2 1 d y = ∫ d x ⇒ ∫ 2 y 4 1 d y + ∫ 4 − y 8 1 d y = x + C (C constant) ⇒ 8 1 ⋅ ( ln ∣ y ∣ − ln ∣ 4 − y ∣ ) = x + C ⇒ e 8 1 ⋅ ln ∣ 4 − y ∣ ∣ y ∣ = K e x (K constant) ⇒ I'm going to consider A = 4 − y y > 0 , if it was A < 0 we can reason in the same way and we would get the same result. it depends on y(2016) = 1 ( 4 − y y ) 8 1 = K e x ( y ( 2 0 1 6 ) = 1 ⇒ K = 0 ) ⇒ Powering to 8 and rearranging y ⋅ ( 1 + k e 8 x ) = 4 k e 8 x (k constant) k = 0 ⇒ y = 1 + k e 8 x 4 k e 8 x ⇒ x → ∞ lim y = 4 . If we consider this equation like a logistic differential equation about the population growth, it could be interpreted saying that the population in "the end of the world" will be 4 times the currently population