kill(all);

van=facebook.com/LearningCalculus$

f(u):= sin(6*u) + 3*u**2 - 2*(u)**3;

integrate(f(u),u,0,1);

integrate(-0.3583*x + 0.7571, x, 0, 1);

float(%);

g(u):= 3*u**2 - 2*(u)**3;

integrate(g(u),u,0,1);

plot2d([g(x)], [x,0,1],
 [plot_format, gnuplot],
 [gnuplot_postamble, "set zeroaxis;"])$