ft <- expression(2*log(t)+log(t^2+t+1)/2-atan((2*t+1)/sqrt(3))/sqrt(3))
D(ft,"t")
    2 * (1/t) + (2 * t + 1)/(t^2 + t + 1)/2 - 2/sqrt(3)/(1 + ((2 * 
    t + 1)/sqrt(3))^2)/sqrt(3)
f1 <- function(t) 2*(1/t)+(2*t+1)/(t^2+t+1)/2-2/sqrt(3)/(1+((2*t+1)/sqrt(3))^2)/sqrt(3)
f2 <- function(t) (3*t^2+2*t+2)/(t^3+t^2+t)
plot(f1,-10,10, col="blue")
# Vedo che il grafico di f2 si sovrappone
plot(f2,-10,10,col="red",add=TRUE)