We'll recall the reminder
theorem:
f(x) = (x+2)^2*Q(x) +
0
Since x = -2 is the root of the polynomial, then the
reminder is 0.
Since the order of multiplicity of the root
is 2, then the quotient is a polynomial of degree 4.
f(x) =
(x+2)^2*(ax^4+bx^3+cx^2+dx+e)
To determine the quotient,
we'll have to calculate the coefficients a,b,c,d,e.
We'll
expand the square:
f(x) =
(x+2)^2*(ax^4+bx^3+cx^2+dx+e)
f(x) = (x^2 + 4x +
4)*(ax^4+bx^3+cx^2+dx+e)
We'll remove the
brackets:
f(x) = ax^6 + bx^5 + cx^4 + dx^3 + ex^2 + 4ax^5 +
4bx^4 + 4cx^3 + 4dx^2 + 4ex + 4ax^4 + 4bx^3 + 4cx^2 + 4dx +
4e
f(x) = ax^6 + x^5*(4a+b) + x^4*(c + 4b + 4a) + x^3*(d +
4c + 4b) + x^2*(e + 4d + 4c) + x*(4e + 4d) + 4e
Comparing
both sides, we'll get:
a =1
4a
+ b = 4 => b = 0
c + 4b + 4a = 1 => c + 4 = 1
=> c = -3
d + 4c + 4b = -12 => d - 12 = -12
=> d = 0
e + 4d + 4c = -11 => e - 12 = -11
=> e = 1
4e + 4d = 4
e
+ d = 1 => e = 1
The requested
quotient is: Q(x) = x^4 - 3x^2 + 1.
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