微积分xdx/(1+cosx)

微积分xdx/(1+cosx)
微积分xdx/(1+cosx)

微积分xdx/(1+cosx)
∫xdx/(1+cosx)
=∫xdx/[2cos²(x/2)]
=∫xd[tan(x/2)]
=x*tan(x/2)-∫[tan(x/2)]dx
=x*tan(x/2)+2*ln|cos(x/2)|+C

用万能代换公式把cosx换成有理式