We'll write the rule of division with
reminder:
P(x)=Q(x)*C(x)+R(x), where the degree of the
polynomial
R(x)<the degree of the polynomialQ(x).
Because the degree of Q(x) is 3, so the degree of R(x) is
2.
R(x)=ax^2+bx+c
We'll
calculate the root of Q(x):
(x-1)*x^2 =
0
We'll set each factor as
0:
x-1 = 0
x1 =
1
x^2 = 0
x2=x3 =
0
The roots of Q(x) are: x1=1,
x2=x3=0.
If we'll substitute x=1 in P(x), we'll
obtain:
P(1)= 1+2-5-10+2
But
P(x)=Q(x)*C(x)+R(x), P(1)=0*C(x)
+a+b+c=a+b+c
a+b+c=-10
(1)
P(0) =
c
P(0)=2
c=2
If
x=0 is a multiple root, this one has to verify the first derivative
,too.
P'(0) =
0
P'(x)=2002x^2001+4000x^1999-25x^4-20x=-2a+b
-2a+b
= 0 (2)
But from (1) and
c=2=>a+b+c=-10=>a+b+2= -10=>a+b=-12
(3)
We'll subtract (2) from
(3):
a+b+2a-b = -12-0
We'll
eliminate like terms:
3a =
-12
We'll divide by
3:
a =
4
We'lll substitute a=4 in
(2):
-2*4+b =
0
b =
8
R(x)=4x^2+8x+2
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