单项选择题
A.2x2dx B.6x2dx C.3x2dx D.x2dx
设y=3+x2,则y'=()A.2xB.3+2xC.3D.x2
单项选择题设y=3+x2,则y'=()
A.2x B.3+2x C.3 D.x2
=()A.eB.1C.e-1D.-e
=()
A.e B.1 C.e-1 D.-e