@ @QRU@ @pý†bɾa@ @
x2 + ax + 1 = x 2 − x − a
ax + x + a + 1 = 0
x(a + 1) + (a + 1) = 0
(x + 1)(a + 1) = 0
.a = −1 x = −1
. x 2 − x + 1 = 0 a = −1
. ∆ = 1 − 4 = −3 < 0
x = −1
.a = x2 − x = (−1)2 − (−1) = 2
x 2 + 2x + 1 = 0
(x + 1)2 = 0
x = −1
x2 −x −2 = 0
(x − 2)(x + 1) = 0
x =2 x = −1
.x = −1