1、【教學目標】(ab) C a C a b C a b C b (n N ) n0n1n11knkknn*nnnn( )a b Cknnk ,nk1(TC a bkknkk1nT C a b .knkkk1nn1.na bn 與 .anb 1 n1 .C ，C C ，Cn .01n1nnnn C C.mnmnn1 / 10n1n1kC kk22nnC 2n當 nn1n1n當 C 2 和C 2nn(ab)n2nC C CCkn Cn2 .012nnnnn即.n 1C C C C C C 2135024nnnnnn11 (x31： )x )7x(x2)6x ()312：x )的展開式中的常數項為()

2、410 x( a 2 )30 ()a3(1 x) (1 x)6x 32 / 10(1x) (1x)6 x53(1)n x 9 n x 1 )n64，則展開式的常數項為()x(1xx) a a (xa (x a (x a62701273(x (x (xa x a x a x a x a xa (a)53543254321028(1x) (1 x) (1 x) (x)3420053C4C4C3C3200520062005200651f(x) x cf(x)f2)5 33xx3()( 2x 3y) 31001( x )n 24 x3 / 10(13 ) xn 36(x(2xa(5)nx x M M

3、N 240N(12x) a a xa x a x7a a a720127127(x x a a (xa (x a (x a (x11a a a a 2923012311123為(3x a x a x a xaa a a7767610137(2 3x) a a xa x a x 1002100012100；a0a a a a1；23a a a a ；135(a a a ) (a a a )2；2021001399|a |a |a |014 / 10(2x a a xa x a x5520125a a a a a ；01234|a |a |a |a |a |a |；012345a a a ；135

4、(a a a ) (a a a )22024135(2x a a (xa (x a (x100a a a a1002012100135(1xx ) a a xa x a x2na a a a2n12n20122n135a a (xa (x a (x (x 2x6a i ( 02212201212i則a a a a a ()2345 a a x a x 25 a x a a 2a a 4a 5a 3 2x50125012345(1 x)十(1x) (1 x) a a xa x a xa a a ，an1n2n2n012n123n(1x)(1 x) (1 x) (1 x) a a xa x a x

5、 a x23n23n0123na a a n n12n15 / 10【課后練習】(1 ) xn13 9 312nnnnn除877()1iz (1i)2z) 5z()71iii (x x a a (xa (x a (x a (xa a a a (292311012311123)21(a )a8 a4x9x a a (xa (x a (x3a a a a 3201231234(12x) (1x) a a xa x a x7a a a a a a a 252012712345676 / 10(x2009 C5；x20042009x(x2009(3 x 2 15 x2( x ) (nN )*nx2x321：若C2n620C (nN) x) a a xa x a x a a a ( a (n2n2nn20012n012n)7 / 10(12x) a a xa x a x a x (xR)201122010201101220102011(a a )(a a )(a a ) (a a )(a a )01020300(x (x a a (xa (x a (xa a a482120121224( ( 3且 n N )xnn*式(xn1 p