\(y = {\cot ^2}\dfrac{2}{x} + \tan \dfrac{{x + 1}}...

Câu hỏi: y=cot22x+tanx+12.y=cot22x+tanx+12. 

A 4cot2x1x2sin22x+12cos2x+124cot2x1x2sin22x+12cos2x+12

B 2cot2x1x2sin22x+12cos2x+122cot2x1x2sin22x+12cos2x+12

C 4cot2x1x2sin22x12cos2x+124cot2x1x2sin22x12cos2x+12

D 4cot2x1x2sin22x+2cos2x+124cot2x1x2sin22x+2cos2x+12