∫ ( sinx+x)/(1+cos2x) dx
=∫ ( sinx+x)/[ 2(cosx)^2] dx
=(1/2) ∫ sinx/(cosx)^2 dx + (1/2)∫ x/(cosx)^2 dx
=-(1/2) ∫ dcosx/(cosx)^2 + (1/2)∫ xdtanx
=(1/2)[ 1/cosx] + (1/2)xtanx - (1/2)∫ tanx dx
=(1/2)[ 1/cosx] + (1/2)xtanx + (1/2)ln|cosx| + C
这种题最好发图片