求不定积分2x-5 x^2-5x 7-搜答案-灵鹊做题网

详见：http://hi.baidu.com/xxllxhdj/blog/item/0f5c8a0c96aab9c762d986c5.html

点小图看大图

∫1/(x^2+2x+5)dx=∫1/[(x+1)^2+4]dx=∫(1/4)/[[(x+1)/2]^2+1]dx=∫(1/4)·2/[[(x+1)/2]^2+1]d((x+1)/2)=(1/2)∫1

令1＋x＝√6sinu,则：u＝arcsin［（1＋x）/√6］,dx＝√6cosudu.∴∫［1/√（5－2x－x^2）］dx＝∫｛1/√［6－（1＋x）^2］｝dx＝√6∫｛1/√［6－6（sin

求sinx/x^2不定积分

∫arcsinx/×2DX=-∫arcsinxd（1/x）的=-（1/x）的*arcsinx+∫（1/X）D（arcsinx）=-arcsinx/X+∫（1/X）*[1/√（1-X2）]DXX=圣马丁

原式=∫(x+1)/x²+∫xlnxdx=∫x/x²+∫1/x²+1/2∫lnxdx²=∫1/x+∫1/x²+1/2*x²lnx-1/2∫x

∫2x*sin(x²)dx=∫sin(x²)dx²=-cos(x²)+C

1/(x+1)(x+2)(x+3)=1/(x+1)[1/(x+2)-1/(x+3)]=1/[(x+1)(x+2)]-1/[(x+1)(x+3)]=1/(x+1)-1/(x+2)-1/2[1/(x+1)

求不定积分dx/x^2

∫dx/x^2=∫x^(-2)*dx=1/(-2+1)*x^(-2+1)+C=-1/x+C

先用分部积分法,然后用t=1-5x^2简化,结果记得换回x　　我算的结果1/4(1-5x^2)^10*x^4-1/1200x^6+1/1100x^(11/2)　　希望对你有用

原式=∫x^(1/2)*(x^2-5)dx=∫[x^(5/2)-5x^(1/2)]dx=2/7*x^(7/2)-10/3*x^(3/2)+C

分部积分法∫xe^x/(1+x)^2dx＝－∫xe^xd[1/(1+x)]＝－xe^x/(1+x)＋∫(1+x)e^x×1/(1+x)dx＝－xe^x/(1+x)＋∫e^xdx＝－xe^x/(1+x)

∫(1/x^2+6x+5)dx=∫(1/[(x+5)(x+1)]dx=1/4∫(1/(x+1)-1/(x+5)dx=1/4[ln(x+1)-ln(x+5)]+C非要用什么换元法的话,令x+1=t,dx

∫dx/(4x-x^2)=∫dx/[x(4-x)]=(1/4)∫[(4-x)+x]/[x/(4-x)]dx=(1/4)∫[1/x+1/(4-x)]dx=(1/4)[ln(x)-ln(4-x)]+C=(

4*x^(1/2)4倍根号X

答：1.原式=∫1/[(x+1)^2+4]dx=1/4∫1/[((x+1)/2)^2+1]dx=1/2*arctan[(x+1)/2]+C2.原式=1/2∫1/x-x^6/(x^7+2)dx=1/2[

解∫x/(x^2)dx=∫1/xdx=ln|x|+C

设(2x²-3x-3)/[(x-1)(x²-2x+5)]=[a/(x-1)]+[(bx+c)/(x²-2x+5)]则2x²-3x-3=a(x²-2x+