不定积分：∫dx/(3+sin^2x)=

∫dx/(3+sin^2x)=∫dx/(4-cos^2x)∫dx/[2+cosx)][2-cosx]=∫(1/4)/[2-cosx]+(1/4)/[2+cosx]dx=(1/4)∫1/[2-cosx]+1/[2+cosx]dx=(1/4){{2/3^(1/2)arctan{[(2+1)/(2-1)]^(1/2)tan(x/2)}}+{2/3^(1/2)arctan{[(2-1)/(2+1...