restart;
plot(exp(t), t = -5 .. 5);
plot(t, t = -5 .. 5);
plot(t*exp(t), t = -5 .. 0);
limit(t*exp(t), t = -infinity);
limit(-y*exp(-y), y = infinity);
plot(t^2*exp(t), t = -5 .. 1);
plot(t^3*exp(t), t = -5 .. 1);