Đặt $\sqrt x = t \Rightarrow dx =2tdt$$I=2\int_0^1 \dfrac{(1+t^2).t}{1+t}dt=2\int_0^1 \bigg (t^2-t+2 +\dfrac{2}{t+1} \bigg)dx=2(\dfrac{1}{3}t^3-\dfrac{1}{2}t^2+2t+2\ln|t+1|)\bigg |_0^1=...$ Tự thay số nhé
Đặt $\sqrt x = t \Rightarrow dx =2tdt$$I=2\int_0^1 \dfrac{(1+t^2).t}{1+t}dt=2\int_0^1 \bigg (t^2-t+2 +\dfrac{2}{t+1} \bigg)dx=2(\dfrac{1}{3}x^3-\dfrac{1}{2}t^2+2t+2\ln|t+1|)\bigg |_0^1=...$
Đặt $\sqrt x = t \Rightarrow dx =2tdt$$I=2\int_0^1 \dfrac{(1+t^2).t}{1+t}dt=2\int_0^1 \bigg (t^2-t+2 +\dfrac{2}{t+1} \bigg)dx=2(\dfrac{1}{3}
t^3-\dfrac{1}{2}t^2+2t+2\ln|t+1|)\bigg |_0^1=...$
Tự thay số nhé