(1)
D
D > 0 (1) : , (2)
> 0, , , .. . a < 0, , , , X .
D = 0 :
= , .
D < 0 , , (2).
> 0, , , , . < 0, , .
( x1, 2 )
:
=
:
:
a > 0, = , ( D ). a < 0, , .
.
2.
: ( - 1)( - 2)( - 3)( - 4) = 15 | ||
: | ||
x1 x2 . , . | ||
, 2 2 + 3 + = 0 . | ||
x 2 + ax + 1 > 0 | ||
, 2. | ||
S ? ? | ||
? . | ||
, . | ||
1, 2 2 2 2(2 + 1) + ( 1) 1 < < 2? |
2.
, | ||
, 2 5 + 6 2 = 0 100. | ||
, . | ||
: . | ||
2 3 + 2 < 0 2 (3 + 1) + 3 ≥ 0? | ||
1, 4 2 2 + 2 2 4 + 3 = 0 | ||
, [-1;1] | ||
, 1 | ||
( + 4) 2 + 6 1 = 0 ? |
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