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Let $f(x) = x^{10}+5x^9-8x^8+7x^7-x^6-12x^5+4x^4-8x^3+12x^2-5x-5$.

User Nex
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1 Answer

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The remainder when
\(f(x) = x^(10) + 5x^9 - 8x^8 + 7x^7 - x^6 - 12x^5 + 4x^4 - 8x^3 + 12x^2 - 5x - 5\) is divided by
\(x^2 - 1\) is 0.

Given the polynomial
\(f(x) = x^(10) + 5x^9 - 8x^8 + 7x^7 - x^6 - 12x^5 + 4x^4 - 8x^3 + 12x^2 - 5x - 5\).

1. Remainder when divided by x - 1:

Substitute x = 1 into f(x):


\[ f(1) = 1^(10) + 5(1)^9 - 8(1)^8 + 7(1)^7 - (1)^6 - 12(1)^5 + 4(1)^4 - 8(1)^3 + 12(1)^2 - 5(1) - 5 \]

f(1) = 0

2. Remainder when divided by x + 1:

Substitute x = -1 into f(x):


\[ f(-1) = (-1)^(10) + 5(-1)^9 - 8(-1)^8 + 7(-1)^7 - (-1)^6 - 12(-1)^5 + 4(-1)^4 - 8(-1)^3 + 12(-1)^2 - 5(-1) - 5 \] \[ f(-1) = 14 \]

3. Remainder when divided by
\(x^2 - 1\):

The remainder is the product of the remainders from steps 1 and 2:


\[ \text{Remainder} = R_1 * R_2 = 0 * 14 = 0 \]

Therefore, the remainder when
\(f(x)\) is divided by
\(x^2 - 1\) is 0.

The complete question is:
Let f(x) =
x^(10)+5x^9-8x^8+7x^7-x^6-12x^5+4x^4-8x^3+12x^2-5x-5 find the remainder when is divided by
x^2 -1.

User Hotel
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