求y=xtanx/1+x²的导数

Question

如题所述

Answer 1

y= (xtanx)/(1+x²)
y ′ = { (tanx+xsec²x)(1+x²) - 2x²tanx } / (1+x²)²
= { tanx+xsec²x+x²tanx+x³sec²x- 2x²tanx } / (1+x²)²
= { tanx+xsec²x-x²tanx+x³sec²x } / (1+x²)²本回答被网友采纳