kill(all)$

fpprintprec:4$

van=facebook.com/LearningCalculus$

f(x):=sqrt(1+x^2)$

F(x):=integrate(''(f(x)),x)+C;

F(x):=fullratsimp(log(x+f(x))/2 +x*log(x+f(x))/2+C);

F(%theta);

F(1)-F(0);

float(%);

float(F(-100));

float(F(100));