A.e^x+2                                         B.e^x+4                                                                     C.2e^x+2                                     D.2e^x+4

14. 当 | | 很小且 f’(x₀) , 函数在 x=x₀ 处改变量 y 和微分 dy 的关系是 (         )

A. y<dy                      B. y>dy                           C. y=dy             D. y dy

15. 设 y=sin²x+cosx², 则 dy=(         )

A.sin2x-2xsinx²dx                                             B.(sin2x-2xsinx²)dx

C.sin2x+2xsinx²dx                                            D.(sin2x+2xsinx²)dx

16. 设 y=ln(1+2x), 则 =(         )    

A.                                                     B.