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.x5 + x4 +1 @ @¶ìÿa@óÝy‹¾a@ u@ @QXV
x2 + x +1
()

x3 −x +1 +1
x2 + x +1 x5 + x4

x5 + x4 + x3

− x3 +1

−x3 − x2 −x

x2 + x +1

x2 + x +1

0

.x5 + x 4 + 1 = (x2 + x + 1)(x 3 − x + 1)

( ) x3 −x +1

x(x + 1)(x + 2)(x + 3) = 63 ()

.(x2 + 3x + 2)(x2 + 3x ) − 63 = 0

y = x 2 + 3x

(y + 2)y − 63 = 0 y =7
y2 + 2y − 63 = 0

(y − 7)(y + 9) = 0

.y = −9