:
f ( x ) = a x2 + b x + c
a , b , c .

( ) .
( ) = 2 + + ,
 0 ,  ,  , ,

: //
( - /2 , ( - /2 ))
1- > 0 +
[ = [ ( -/2 , 
2- < -0
 , ( -/2 ) ] = ] -
:
1- 2 4 > (0 ) ( 2 )
 0 2- 2 4 ( ) = 0
:
7172 :
Ý- ( ) = 2- 6
:
, :
4 = 1- 4 * 1 * 1 6 = 25 > 0
2- -6 = 0 ( ) = 0 
= 3 , = -2 , = 1 > 0



:



( 2 ) .
, -2 ] [ ] -  [ 3 ,   0  ( ) 
( ) < ] 2 , 3 [ 0
:
1- ( ) = -4 + 2 + 4
= 2 4 = 16- 4 * 1 * 4 = 0
= 1 > 0
- } {
( ) = 0 2 4 + 4 = 0
= 2( 2 ) ( 2 ) = 0 
( ) > - } 2 { 0
2- ( ) = 2 + + 1
= 2- 4 = 1 4 * 1 * 1 = - 3 < ( ) 0 > 0 ( )
= 1  > 0
7172
) ( 5- ) ( 1 ) = ( )
2-4 >0
= 1 , = 5( 1 ) ( - + 5 ) = 0
= - 1 < 0




( ) > ] 1 , 5 [ 0
( ) < , 1 [ ] -  [  ] 5 ,  0
= 1 , = 5 ( ) = 0
:
1- ( ) = 22 + 3 + 1
2- ( ) = 2 6 2
3- ( ( ) = 2 6 + 5 )
- :
:
- ( ) = + + 0000 + +
 0 , 
 = =
= - } {
:
:
1- ( ) = +1/-4
4  0  4
 = - } 4 {
2- ( ) = - 2 /2+ 2
= - } 1 , - 2 {
:
( ) = 02+4/ 2+5 2+ 5
 
( ) = 



1- = .
2- ( ) > 0
:
:
1- =   ( ) =
2- ( 0  ) =
= [ 0 , [
: 5  5- 3- ( ) = 0
, 5 ] = ] -  5  
9-24- ( ) =
- 3 3  | |  3 
[ -3 , 3 ]  
2- 95- ( ) =
9 2  0  2 9
- 3 3   3  
= , - 3 ] ] -  [ [ 3 ,
-   ] -3 , 3 [
2 3 + 46- ( ) =
0 : 2- 3 + 4
( ) = 2-4 = -7 < 0
 
2 3 + 4 >  0
= 1 > :
7- 2 + 5 + 6 ( ) =
: 2 +5 0 +6
( 2 + 5 + 6 )
= 1 > 2 + 5 +6 = 00
( +2 ) ( +3 ) = 0
= -2 ,  = -3 , = 1 > 0
< > 0 < 0 > 0
( ) > [ - 2 0 , -2 ] ] -  [ ,
1 ] 3 , - 2 [ 
2+ 28- ( ) =
= [ - 1 , 2 ]
9- -1/-2( ) =
:
1  0 -1
 [ = [ 1 ,
 2   0 2- - 2 - } 2 {
= - } {
[ - }2{= [ 1 ,
8- ( )
 ( ) = | | = }
} < 0
= :
( ) = | | 0
  
[ = [ 0 ,









:

( ) = | 5 |
:
| 5 | = } 5 5
} + 5 < 5
=
:
3 4 5 6 7
2 1 0 1 2
= [[ 0 ,
:
.
( ) = | 5 | + 3
5 : | 5 | = } 5
} + 5 < 5
5 ( ) = } 2 
} + 8 < 5
=
:
3 4 5 6 7
5 4 3 4 5
[ = [ 3 ,
:
( ) = | + 3 | + | 3 | + 2


:
( ) = | 2 4 5 | 1 171
: ( 2 4 5 )
= 36 > 0
( 5 ) ( + 1 ) = 02 4 5 = 0
= 5 , = - 1 , = 1 > 0
< *5 *-1 >-
( ) > 0 ( ) < 0 ( ) > 0
( ) = | 2 4 5 |
= } 2-4 5 > 5
5 } ( 2-4-5 ) -1
} 2-4 5 < -1
:
// + = 1 > 0 ( -/2 ) (-/2) )
= ( 2 , 9 ) ( -1 , 0 ) , ( 5 , 0 )
:
- 3 - 2 -1 0 2 3 5 6 7
16 7 0 5 9 8 0 7 16
4 172
( ) = } | 2 7 8 | > 8
8
8} 17-







: .
: ( 2 7 8 )
= 8 , = - 1 2 7 8 = 0
 > 0 = 1 > 0
< *8 *-1 >-


> 0 < 0 > 0
|2- 7  8 | = } 2- 7 8 > 8
8
8} 17-
= } ( 8 ) ( + 1 ) > 8
( 8 )
817-
= } +1 > 8
8} 17-

[ = = [ 9 ,
10 9 8 7 6
11 10 9 10 11




- -


- -

- - - .

( ) = 2 + 2 - 3


( ) = + 1