syms v(t) s(t)
g = 9.8;
EQv = diff(v) == -g;
cond = v(0) == 105;
v(t) = dsolve(EQv, cond)
EQs = diff(s) == v(t);
cond = s(0) == 0;
s(t) = dsolve(EQs, cond)
tmax = 150/7
tmax = 21.4286
syms vr(t) sr(t)
k = 0.003;
EQv2 = diff(vr) == -g-k*vr;
cond = vr(0) == 105;
vr(t) = dsolve(EQv2,cond)
EQs2 = diff(sr) == vr;
cond = sr(0) == 0
sr(t) = dsolve(EQs2,cond)
fplot(s(t), [0 tmax], 'Color', 'blue', 'LineWidth', 2)
hold on
r = solve(sr(t)==0)
sr
fplot(sr(t),[0 double(r)], 'Color', 'red', 'LineWidth', 2) % interval should be double to avoid warning
legend('Sin resistencia','Con resistencia')
hold off