∫dx (1 ³√x 1)的不定积分-搜答案-拍题作业网

∫(1+cosx^3)dx=x+∫cosx^3dx=x+∫(1-sinx^2)dsinx=x+sinx-(sinx)^3/3+C再问：∫(1+cos3x）sec2xdx我看习题的答案为什么下一步就是∫

答：原式=∫(1+sinx-1)/(1+sinx)dx=∫1-1/(1+sinx)dx=∫1-1/(1+cos(x-π/2))dx由cos2t=2(cost)^2-1可得：=∫1-1/(1+2[cos

再答：再答：再问：答案是这个

∫1/(1+e^x)dx=∫1/[e^x(1+e^x)]d(e^x)=∫[1/e^x-1/(1+e^x)]d(e^x)=x-ln(1+e^x)+C

你的答案也是对的,等价的你的答案:∫1/(2x+3)dx=1/2∫1/(x+3/2)d(x+3/2)=1/2ln|x+3/2|+C'=1/2ln|(2x+3)/2|+C'=1/2(ln|2x+3|-l

原积分=∫(1,0)（x+1)dx+∫(2,1)(1/2x^2)dx=(1/2*x^2+x)(1,0)+(1/6*x^3)(2,1)=(1/2+1/2)+(1/6*8-1/6*1)=13/6PS:这个

我的解答如下：换元法令x=3/2sint,t∈[-0.5π,0.5π]dx=3/2cost带入后得到∫(1-x)/[√(9-4x^2)]dx=∫(1-1.5sint)1.5costdt/3cost=∫

原式=(1/2)∫d(2x+1)/√(2x+1)=(1/2)*2*√(2x+1)+C(C是任意常数)=√(2x+1)+C.

答：∫[x/(1-x)]dx=∫[(x-1+1)/(1-x)]dx=∫[-1+1/(1-x)]dx=-∫dx-∫[1/(x-1)]d(x-1)=-x-ln|x-1|+C

第一题：原式＝2∫｛x^2/［x（x－4）］｝dx－∫｛1/［x（x－4）］｝dx　　＝2∫［x/（x－4）］dx－（1/4）∫｛（x－x＋4）/［x（x－4）］｝dx　　＝2∫［（x－4＋4）/（x

∫√（1+cosx）dx=∫√（2*cos2(x/2)）dx=∫√2*cos(x/2)）dx=∫2√2*cos(x/2)）d(x/2)=∫2√2*dsin(x/2)=2√2*sin(x/2)+常数

1-sin2x=sin^2(x)+cos^2(x)-2sinxcosx=(sinx-cosx)^2∫[√（1-sin2x)]dx=∫|sinx-cosx|dx后面好像要分区间讨论了,你自己看着办吧

∫x^2/√(1-x^2)dx=-∫-2x^2/2√(1-x^2)dx=-∫xd√(1-x^2)=-x√(1-x^2)+∫√(1-x^2)dx其中,解∫√(1-x^2)dx令x=sintdx=cost

∫√(1-sin2x)dx=∫Isinx-cosxIdx=Isinx+cosxI+C

=∫(x^2-4x+4)*x^(-1/2)dx=∫[x^(3/2)-4x^(1/2)+4x^(-1/2)]dx=2x^(5/2)/5-8x^(3/2)/3+8x^(1/2)+C=2x^2√x-8x√x

∫1/(1+e^x)dx＝∫e^(-x)/(1+e^(-x))dx＝-∫1/(1+e^(-x))d(1+e^(-x))＝-ln(1+e^(-x))＋C＝-ln((1+e^x)/e^x)＋C＝x-ln(

令x=sect,dx=sect*tantdt,原式=∫sect*tant/sect√sec^2t-1dt=∫dt=t+Ccost=1/x,则t=arccos(1/x)