Page 130 - aljaber
P. 130
@ @QQW@ @pý†bɾa@ @
:() ( )
x2 + x − 5 = 3x + c
x 2 − 2x − (c + 5) = 0
. ∆ = 4 + 4(c + 5) = 24 + 4c
.c > −6 .∆ > 0
.( )
2x2 − 3x − 4 = 0 β α :( ) ()
. αβ = −2 α+β = 3
2
11
βα
a≠0 a x − 1 x − 1 = 0
α β
x − 1 x − 1 = 0
α β
αx − 1 βx − 1 = 0
α β
(αx − 1)(βx − 1) = 0
αβx2 − (α + β)x + 1 = 0
−2x2 − 3 x + 1 = 0
2
. 4x2 + 3x − 2 = 0
.x :( ) ( )
x −7
.x + 2