suy ra x=$\dfrac{1}{4}\left ( t-\dfrac{1}{t} \right )^{2}$
I=$\dfrac{1}{2}\int \dfrac{t^{4}-1}{t^{4}+t^{3}}dt$
tinh toan cho ta I=$\dfrac{t}{2}-\dfrac{1}{2}\ln t-\dfrac{1}{2t}+\dfrac{1}{4t^{2}}$=
$\dfrac{\sqrt{x}+\sqrt{1+x}}{2}-\dfrac{1}{2}\ln \left |
\sqrt{x}+\sqrt{1+x} \right |-\dfrac{1}{2\left (
\sqrt{x}+\sqrt{1+x}\right )}+\dfrac{1}{4\left (
\sqrt{x}+\sqrt{1+x}})^{2}$
- NguyThang khtn yêu thích