Chủ đề này có 1 trả lời

[queo]

$\int\limits_{1}^{2}\dfrac{x^2}{\sqrt{x^3+2}}dx$
minh quen cach giai rui!!!

[E. Galois]

$\int\limits_{1}^{2}\dfrac{x^2}{\sqrt{x^3+2}}dx$
minh quen cach giai rui!!!

$\int\limits_1^2 {\dfrac{{x^2 }}{{\sqrt {x^3 + 2} }}dx = } \dfrac{1}{3}\int\limits_1^2 {\left( {x^3 + 2} \right)^{ - \dfrac{1}{2}} d\left( {x^3 + 2} \right) = } \dfrac{2}{3}\left. {\sqrt {\left( {x^3 + 2} \right)} } \right|_0^1 = \dfrac{{2(\sqrt 3 - \sqrt 2 )}}{3} $