Question

What is the limit of `arccos((1+x^2)/(1+2x^2))` as x goes to infinity?

Answer 1

`pi/3`

Explanation:

`arccos ((1+x^2)/(1+2x^2))= arccos((1/(x^2) +1)/(1/x^2 +2))`.

Now apply the limit `x->oo`, it would be `arccos(1/2)=pi/3`