save_figs = F

r1 = -2
r2 = 1/2
A = 3/5
B = 2/5

t_y_min = (2/5) * log(6)
print(t_y_min)

ts = seq( 0, 3, length.out=100 )
ys = A * exp(r1 * ts) + B * exp(r2 * ts)
if( save_figs ){ postscript("../../WriteUp/Graphics/Chapter3/chap_3_sect_1_prob_25_plot.eps", onefile=FALSE, horizontal=FALSE) }
plot(ts, ys, type='l', xlab='t', ylab='y(t)', main='Question 25')
abline(v=t_y_min, col='red')
grid()
if( save_figs ){ dev.off() }