A.(x-2y)y′=2x-y
B.(x-2y)y′=2x
C.xy′=2x-y
D.-2yy′=2x-y
[单选题]A.(x-2y)y′=2x-yB.(x-2y)y′=2xC.xy′=2x-yD.-2yy′=2x-y
[单选题]A.<10μmB.10~60μmC.70~100μmD.200~300μmE.>300μm
[单选题]A.(x-2y)y′=2x-yB.(x-2y)y′=2xC.xy′=2x-yD.-2yy′=2x-y
[单选题]A.(x-2y)y′=2x-yB.(x-2y)y′=2xC.xy′=2x-yD.-2yy′=2x-y
[单选题]A.绝对收敛B.条件收敛C.发散D.