1 ( ) 18 MA 2009 : : (4)

1o A. ()=()+() 10

B.

x 1 ,x 2 ,,x X (), f i x i , i=1,2,,. 5 , . . f, g (f ( x )g( x ) ) = f ( x )g( x ) + f ( x )g( x ) 2 . A , , A B = A B 2

.

1 4

2

. f(x)=x (x ) = x 2 . . 2 . . 2

2 x i , i=1,2,3,4 i , i=1,2,3,4. 2 x 2 =3 . =4. x xi 2 3 5 8 . 2 =7. i 6 ; 3 4 9

. 4,9. 9 . X . 4,9 2,2 7

2 4

3

3o f(x)=x36x2+x7, ,

2f ( x ) + f ( x ) + 15 = 3x 2 , x . =9 7 . lim

f ( x ) x 1 x 2 1

8

. f, y=3x 10 4 f(x)=lnx .

x + 2 6+2, x>0 2

. . f f . 6 . f . 6 . f(2), f(4), f(8), f(3) f(5) . . R , R=3+ ln

1 = ln4+ 2 6 4 7

3 4

4

. ={1,2,3,,100} . A , ={ | R+