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. f (x) = (x − 3)(x + 3)q(x) + r(x)
f (−3) = −35 ×a − 33 ×b − 3c
( )= − 35 ×a + 33 ×b + 3c
= −f (3) = −6
6 = f (3) = r(3)
−6 = f (−3) = r(−3)
.r(x) = ax + b . degr(x) < 2
r(3) = 6 ⇒ 3a + b = 6
r(−3) = −6 ⇒ −3a + b = −6
.a = 2 . 6a = 12
.r(x) = 2x .b = 0
. f (x) = x 8 :( ) ( )
f (x) = x8 = x + 1 q1(x ) + r1
2
. r1 = f − 1 = − 1 8 = 1 8
2 2 2
. f (x) = x8 = x + 1 q1(x ) + 1 8
2 2
x + 1 q1(x ) = x8 − 1 8
2 2
= x − 1 x + 1 x 2 + 1 2 x 4 + 1 4
2 2 2 2