∫dx 根号(9-4x²)-搜答案-智慧作业帮

令u=√v,v=4x²+1,dv=8xdx∫√(4x²+1)dx=∫√v*1/(8x)*dv,这个x无法抵消,所以要用另一种代换法√(4x²+1)=√[(2x)²

令√x=tx=t^2dx=2tdt原式=∫2tdt/(1+t)=2∫[1-1/(1+t)]dt=2t-2ln(1+t)+C

∫dx/根号(4x-x^2)

∫dx/√(4x-x^2)=∫dx/√([4-（x-2）^2]=arcsin[(x-2)/2]+C

∫1/(1+2根号x)dx

令t=√x∫1/(1+2√x)dx=∫1/(1+2t)dt^2=∫2t/(1+2t)dt=∫1-1/(1+2t)dt=∫dt-∫1/(1+2t)dt=t+1/2ln(1+2t)+C=√x+1/2ln(

$x[(x)^(1/2)+1)]dx=$[(x^(3/2)+x]dx=(5/2)*x^(5/2)+x^2/2(积分号9到4)=(5/2)*(9)^(5/2)+(9)^2/2-(5/2)*(4)^(5/

求∫dx/1+(根号x)

解令√x=t则t²=x,dx=2tdt∴∫dx/(1+√x)=∫2tdt/(t+1)=2∫[(t+1)-1]/(t+1)dt=2∫1-1/(t+1)dt=2t-2ln|t+1|+C=2√x-

∫lnx/√xdx=2∫lnxd(√x)分部积分=2√xlnx-2∫√x/xdx=2√xlnx-2∫1/√xdx=2√xlnx-4√x+C希望可以帮到你,如果解决了问题,请点下面的"选为满意回答"按钮

设√（5-4x）=yx=(5-y²)/4dx=-ydy/2则∫x/√(5-4x)dx=∫(5-y²)(-ydy/2)/4y=∫(y²-5)dy/8=y³/24-

分部积分法：∫√(9+x^2)dx＝x√(9+x^2)dx－∫x^2/√(9+x^2)dx＝x√(9+x^2)dx－∫(9+x^2-9)/√(9+x^2)dx＝x√(9+x^2)dx－∫√(9+x^2

(x^2)/2-18x^(1/2)+3x+C0.5*x^2+2*x^(1/2)+C9x-2x^3+0.2*x^5+C

∫1-x/√(9-4x²)dx＝=x+√(9-4x²)/4

令x=2siny,则y在0到pi/2之间∫根号下(4-x^2)dx[0,pi/2]=[2y|0,pi/2]+[sin(2y)|0,pi/2]=pi

解∫x√(4x²-1)dx=1/8∫√(4x²-1)d(4x²-1)=1/8∫√udu=1/8×(2/3)×u^(3/2)+C=1/12(4x²-1)^(3/2

∫√(x²-9)/xdx=√(x²-9)-3arcsec(x/3)+C

∫dx/(根号5-4x-x^2)=积分1/根号(3^2-(x+2)^2)d(x+2)=1/3积分1/根号（1－[（x＋2）/3]^2)d(x+2)=积分1/根号（1－[（x＋2）/3]^2)d[(x+

令x=2sint则dx=2costdt原式=∫2cost*2costdt=2∫(1+cos2t)dt=2[t+0.5sin2t]+C=2t+sin2t+C=2arcsin(x/2)+2*x/2*√(1

令x＝3/（2cosu）,则：cosu＝3/（2x）,dx＝3｛sinu/［2（cosu）^2］｝du.∴∫｛1/［x^2√（4x^2－9）］｝dx＝∫｛（2cosu/3）^2/√［9/（cosu）^

∫dx/√(4x^2+9)设√(4x^2+9)=tx=√t^2-9)/2dx=t/2√(t^2-9)dt带入得∫dx/√(4x^2+9)=∫1/2√(t^2-9)dt=lnΙt+√(t^2-9)Ι+c