∫[-π/2,π/2 ](1+x^3)cosx/(1+sin^2 x)dx =∫[-π/2,π/2 ]cosx/(1+sin^2 x)dx +∫[-π/2,π/2 ]x^3cosx/(1+sin^2 x)dx （注意后面一项是奇函数,等于0）=∫[-π/2,π/2 ]cosx/(1+sin^2 x)dx=∫[-π/2,π/2 ]1/(1+s...