99 cjt h. 4 (79 ) 4 88 88. 0 0 7 7 7 ( ) (80 ). ( ) (8 ) 4! ( ) 0 4 0 4. n (x)(x) (x) n x an bn cnd abcd (8 ) () adbc () acbd () ac (4) db0 () abcd (x)(x) (x) n n ( x)[ ( x) ] ( x) ( x) ( x) x) ( x) n + n + n n + ( ) 0 x n + ( x) n + ( x) n+ x n+ (x)(x) (x) n x n+ ( n + ) n( n ) a b0c d0 () n n.4 ( )(8 ) () 4 4 4 4 88 () 4 4 4 4 4 7 887. AB DEF (8 ) () 9 () 4 () (4) 8 () 0 AB DEF 9 A B AB DEF 9 998 (4) D E F
99 cjt h 7. 0 (8 ) 0 () abc a b c abc0 aaa 0 a () bca abc0 aa0 a0 0 a0 abc a789 a 9 9 9 9 8 8 8 7 b 9 8 7 8 7 7 c 4 4 8 8 8. (8 ) 9! 4 8 9 8 9 8 80 80 9. 4 4 (8 )! ()4400 90!!! 4! () 4 444 400!! 90 0. 78 (8 ) n n( n ) n 78 78 (n)(n)0 n ( ). AB090 4 0000 (84 ) () (40-) () 40- () (040-) (4) (9000-) () 9000-0000 0 0 0 (0)9000 (9000) (4) 4. 0400070800900 (84 ) () 0 () 8 () () (4) 40 () 4 () 0 () 8 () 7 () 4 (4) 4 ()
99 cjt h ()( )( 0 ) 9 8404 () 0 0 0 0 8 0 0 0 7 874 () () () (4). xyzu 9 (84 ) 9 9 4 4 9! () H k () H k () (4) ()! k= k= (x)(y)(z)(u) xaybzud ABD ABDE ABDE H + 9 () 4. n k nk (nk)(nk)(nk) n (84 ) n k n k n k + n k n k n k n n k + k n k n k + n k n n! n! k n k nk0 () ( k )!( n k)! ( k )!( n k + )! n! n! n k + n k nk0 () ( k + )!( n k )! k!( n k)! ()() n4k 4.(40) () () () 4 (4) () 8 (8 ) (40) (9) 0 4 0 9 0 9 () ( ). 0 0 (8 ) 7. A B (8 ) A 9 B 9 AB 99 A B
99 cjt h4 8.04 () 400 0 ()k 0k 4k (i) 0 4 (ii)0 ( ) 440 0040 (8 ) 9.4 ( ) (8 ) () 0 () 8 () 48 (4) 0 () 48 () 00 () 4 0 0000 (4) 4 0. A B (8 ) A B D EF 4!! ()A D B!!!! A 4! A!! D E! D B F!! 4!! ()A E F B 8!!!! 4! A E!! A! F B 4!! 4 4 80 0 4 0 B 0 0 B A B. 0 0 (8 ) (0 ) (8 ) 0 8 70487 7. (8 ) ABDE DABE D A B E 4 4 490 90 A B D E
99 cjt h. (87 ) 00x0yz xz xz ± x 4 7 8 9 z 0 4 7 4 8 9 7 y 0 9 0 00 0 4. (87 ) D A B () AB G DH FH FG 4 AD B D 4 4 4 H G () AE HG FG 48 84 4 E F. (87 ) 8 8 4 4 0 0. ( ) 4 (88 ) x y ( ) x4y xy xy 0 x 0 4 y 0! 4!!!!!!! 4!! 7. xyz 7 (88 ) (xyz) x + y + z 7 x y z ()(04)! 4 ( )! ()( 4! 4448 48 8. 0 (89 ) () 0 4 0 () 0 4 4 0 0 0 000 00
99 cjt h 9. 9 (90 ) AB AB 9 AB 0 0 0. 4 0 (90 ) () () 4 4 4 4 4 400 400. 00 (9 ) 4 0 ( 0 + ) 0 0 + 0 + L+ 0 + 4 0 + 0 0 00[ 0 + 0 + L + 0 ] + 0 0 + 00 00. cm (9 ) cm 44 0 cm cm 4 8 4 cm 480. 7 (9 D) ( )( )( )( )( )( )( )( )( ) ( )( )( )( )( ) 4. ( ) 0 H 4 + 9 84 4 84 (9 )
99 cjt h7. 8 4 7 8 (9 B) () 4 7 74 () 4 7 4 84 () 4 4 4 4 7 4 484. (9 ) (0 )( 0 ) 0 0 0 7. 4 (94 ) 4!!! 8. --- 70 70 700 700 700 800 800 800 ( ) (9 ) () 800 ( ) ( ) () 700 ( ) ( ) 9. 9 4 (9 ) () (4) () 4 7 40. ( ) (9 )
99 cjt h8 8 4 9 8 0 7 () () () (4) () () 0 () () (4) 4. 0, 000 00, 000 00 000 00. (9 ) () 000 0 () 4 () 000 (4) 000 9 (A) 00 (B) () (D) 0 () 4. 7 (9 )! 7 840 840 4. (9 ) 94
99 cjt h9 44. A B A B (9 ) 4. O 0 9 4 AA4AB444 AO4AB444 A 4 (97 ) () 9 () 9 0 () 900 (4) 990 () 999 A 4 0 0 0 0 0 0 000 A 4 4 4 4 0 0 0 000 0 990 (4) 4. (97 A) 4 n(4 )n ( ) n (4 )[n( )n( )n( )] 4 ( )4(4)0 0 47. 7 7 7 (98 D) 4!! 7 7 48. a a a k a 0 a a a k a 0 (99 ) 0 0 ()0 () () P (4) () 0 0 0 a a a k a 0 0 0 ()0 9 a a a k a 0 9 ()8 8 a a a k a 0 8 () 0 0 a a a k a 0 0 0 () 0 ()
99 cjt h0 49. 4( ) (99 ) () 4 44 ~ 4!=4 () P ()() 44884 4 ~ 4!=4 ~ 4!=4 P 4 88 0.. 8 (99 ) () 4 () 4 ( ) () ( ) 4 4!4 49.abcd 0 p(x)x ax 4 bx cx dx () p(x) (99 ) () x x 4 x 7x x0 ()0 9 0 abcd 0 0 0 0 00000 (). B A (00 ) E () () () 0 (4) 0 () D
99 cjt h AB (AADAE) A E BD BD B B D (DEBE) () (A) (B) () A. AB (0 9) () 8 () A () (4) D H () B E I () 8 () DIF EHG () DEFGHI B () DIF EHG ()() F G 4. (0 ) () 7 () 9 () (4) () () () ()() ().(x y) (0 ) () x 4 x 0 y 7 () x 4 y x 0 y 7 (x y) k k ( x ) y k= 0 () x y x 0 y 7 (4) x 8 y 8 x 0 y 7 k x k ( ) y k x () x 4 x 0 y 7 () x y x 0 y 7 () x 4 y 7 x 0 y 7 7 (4) x 8 y 8 4 x 0 y 7 4 ()(4) k k k y k
99 cjt h. 70 () (0 ) () 70 () () 70 (4) 70 () 70 ~( ) ~ ~ ~ ~( 70 () ) 70 70 ~ ~( ) () () 7.4 () () () (4) 98 () (0 ) ryg raybgcabc ryg4 (a)(b)(c)4 a(bc) a a 9 7 9 7 b 0 ~0 ~0 ~0 4~0 ~0 ~0 7~0 8~0 9~0 0~0 c 0 0~ 0~ 0~ 0~4 0~ 0~ 0~7 0~8 0~9 0~0 4 7 8 9 0 47890 () 8. 8 9 0 (0 A) 4 4 4! 4! 0 4 4 0 9.( + ) ab ab b (0 ) () 0 4 () () 0 4 4 (4) () 0 4 4 ( + ) 0 ( ) ( ) 4 ( ) 4 ( ) ( ) () 0 4 4 4 8 ( 0 4 4 8 )( 4 ) b 4
99 cjt h 0. 8 9 (0 F).79 ( ) 8 9 (0 A) () () abab (,,7,9) ( 4! (! () aaa (,,7,9) ( 4 (,,7,9 (! 49 49