[x?.e- dx :(9)-r d(-x3lefcSer-(10)ddtanxcos?xytanxtanxtanx=2/tanx+c;(11)darcsinxdx(arcsinx)/-x?(arcsinxParcsinx(12)[sin'xcos' xdx =[sin x(1-cos’ x)cos' xdx=-J(1-cos’ x)cos xd cosx1cos"x-cosx+c86(Vx +1)(x- Vx +1)Vx+1(13)dxdb/x +1Vx+1-[(x-x+1)x=→-+x+c;23(14)设x=t,x=t4dx=4t dt,则C.4r3-dx =[dt4-x+4x1+[-1+ldt=4[(-1])d+J,-dtt+1= 2(t? -2t+21n|t+1)+c= 2(Vx-2/x+21n|x+1+c)(15)设x=t,x=t,dx=6tdt,则3/x
(9) 3 2 x x e dx − ( ) 3 1 3 3 x e d x − = − − 1 3 3 x e c − = − + ; (10) 2 1 cos tan dx x x 2 sec 1 tan tan tan x dx d x x x = = = + 2 tan x c ; (11) ( ) 2 2 1 arcsin 1 dx x x − ( ) 2 1 arcsin arcsin d x x = 1 arcsin c x = − + ; (12) 3 5 sin cos x xdx ( ) 2 5 = − sin 1 cos cos x x xdx ( ) 2 5 = − −1 cos cos cos x xd x = 1 1 8 6 cos cos 8 6 x x c − + ; (13) ( ) 3 1 1 x dx x + + ( 1) 1 ( ) 1 x x x dx x + − + = + = − + ( x x dx 1) 1 2 2 3 = 2 3 x x x c − + + ; (14) 设 4 x = t , 4 x t = 3 dx t dt = 4 ,则 4 1 dx x x + 3 4 2 2 1 4 = t dt dt t t t t = + + ( ) 2 1 1 1 4 4[ 1 ] 1 1 t dt t dt dt t t − + = = − + + + = 2 2( 2 2ln 1) t t t c − + + + = 4 4 2( 2 2ln 1 ) x x x c − + + + ; (15) 设 6 x = t , 6 x t = , 5 dx t dt = 6 ,则 ( ) 3 3 x dx x x x + ( ) ( ) 2 2 5 6 6 3 2 6 3 2 (6 ) = t t t dt dt t t t t t t = + +
= 6ln-6ln|t+1|+c/x+1x+1(16)(解法一)x/x/r2d(x-2)+v2x-=2/x-2+2arctan设x-2=t,x=?+2,dx=2tdt,则(解法二)[+2+l,2tdt =2(x+1dx=d2 +(2)1/x-2(t2 +2)t+actanx2x-2)+c=2/x-2+/2arctan= 2(t +V2(17)设x=2sint(t=arcsin)dx=2costdt,则[x?/4-x dx =[4sin?t.2costd2sint=16 sin’t.cos'tdt1- cos 4f t4sin?2tdt=422[| dt-Jcos 4td(4t) =2t-sin4t+c1=2t-↓:2sin 2tcos21+c2=2t-2sint-cost(1-2sin2t)+=2arcsin =-2.二.V4-222--14-V4-x2+=2arcsin242
2 1 1 1 6 6 ( ) 1 dt dt t t t t = = − + + = 6ln 6ln 1 t t c − + + = ( ) 6 6 ln 1 x c x + + ; (16)( 解法一) 1 2 x dx x x + − 1 1 2 2 dx x x x = + − − = ( ) 2 1 1 2 2 2 2 2 2 1 2 x d x d x x − − + − − + = 2 2 2 2 arctan 2 x x c − − + + ; ( 解法二) 设 x − 2 = t , 2 x t = + 2, dx tdt = 2 ,则 2 2 2 2 2 2 1 2 1 2 1 .2 2( ) 2 ( 2) ( 2) 2 x t t dx tdt dt dt x x t t t t + + + + = = + − + + + tan 2 2( ) c 2 x ac = + + = t 2 2 2 2 arctan 2 x x c − − + + (17) 设 x t = 2sin ( arcsin ) 2 x t = , dx tdt = 2cos ,则 2 2 x x dx 4 − 2 2 2 = 4sin 2cos 2sin 16 sin cos t td t t tdt = = 2 1 cos 4 4 sin 2 4 2 t tdt dt − = = cos 4 (4 )] 4 1 2[ dt td t − = 1 2 sin 4 t 2 t c − + = 1 2 2sin 2 cos 2 2 t t t c − + = ( ) 2 2 2sin cos 1 2sin t t t t c − − + = 2 2 4 2arcsin 2 1 2 2 2 2 4 x x x x c − − − + = 3 2 2 2arcsin 4 4 2 2 4 x x x − − + − + x x c ;
(18)(解法X-arcsin=+c;1aX(解法二)设x=asint(t=arcsin=)dx=acostdt,则aVa?-xYa?-(asint)?rcostdt[cot? tdt = [(csc t -1)dtacostdt=(asint)?sin"tcOsX-cott-t+c=-arcsin=+cxsinxaaAJa?-x?-arcsin-+ca(19)设x=tant(t=arctanx),dx=sectdt,则tan"ttant2dtantsecsec-1-cos2t2sin2t+c24x-arctanxFC2(1 +x2)2(解法dxa(20)设XF=xdt=-In+ V1+Vi+t?
(18)( 解法一 ) 2 2 2 a x dx x − 2 2 2 2 2 2 1 1 1 a x d a x dx x x a x = − − = − − − − 1 2 2 arcsin x a x c x a = − − − + ; (解法二) 设 x a t = sin ( arcsin ) x t a = , dx a tdt = cos ,则 2 2 2 a x dx x − 2 2 2 2 2 2 2 (a sin ) cos = a cos cot (csc 1)dt (a sin ) sin a t tdt tdt tdt t t t − = = = − 2 1 ( ) cos cott t c arcsin sin x x x a t c x a x a − = − − + = − − = − − + 1 2 2 arcsin x a x c x a = − − − + (19) 设 x t = tan ( t x = arctan ), 2 dx tdt = sec ,则 ( ) 2 2 2 1 x dx + x 2 2 4 2 tan tan tan sec sec t t d t dt t t = = 2 1 cos 2 sin 2 t tdt dt − = = 1 1 sin 2 2 4 = − + t t c = 2 1 arctan 2 2(1 ) x x c x − + + ; (20) (解法一)设 1 x t = , 1 t x = 2 1 dx dt t = − 2 1 1 dx x x + 2 2 2 2 2 2 1 1 1 1 1 1 1 1 ln 1 1 d t t t t dt t t dt t t c t = + = − + = − = − + + + +