求不定积分 [I(x+x2+1)dx 实买分4 aa n时-gny*-i +nrf时1  ln( x + x +1)dx 求不定积分 2 1 2 0 (1 ) x xe dx + x 计算定积分 1 1 1 2 2 0 0 0 1 1 1 1 2 2 0 0 0 0 1 1 2 2 0 0 ( 1 1) (1 ) (1 ) (1 ) (1 ) (1 ) (1 ) (1 ) 1 (1 ) (1 ) 2 x x x x x x x x x xe x e e dx dx dx xxx e de e e dx dx x x x x e e e dx dx x x + − = = − +++ − = − = + + + + + − = − + +        