Question #496b1

1 Answer
Aug 14, 2017

100e^(-0.2t).100e0.2t.

Explanation:

Given that, (dN)/dt=KN.dNdt=KN.

:. (dN)/N=Kdt,.....".[Separable Variable Type Diff. Eqn.]."

Integrating, int(dN)/N=Kintdt+C.

:. lnN=Kt+C.

:. N=e^(Kt+C)=e^(Kt)*e^C=ce^(Kt)," where, c=e^C."

With, c=100, &, K=-0.2," we have,"

N=100e^(-0.2t).

Hence, the Last Option is the Right Choice.