Tính đạo hàm của hàm số sau y=sin2x+cos2x2sin2x−cos2x.

Chọn D

y'=sin2x+cos2x/.2sin2x−cos2x−2sin2x−cos2x/.sin2x+cos2x2sin2x−cos2x2

y'=2cos2x−2sin2x2sin2x−cos2x−4cos2x+2sin2xsin2x+cos2x2sin2x−cos2x2=4.cos2x. sin2x - 2cos22x−4sin22x+​2.sin2x.cos2x  (2sin2x−cos2x)2− ( 4cos2x . sin2x + 4cos22x+2sin22x+2sin2x.cos2x(​2sin2x−cos2x)2

y'=−6cos22x−6sin22x2sin2x−cos2x2=−62sin2x−cos2x2