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Using the Remainder Theorem find the rem...

Using the Remainder Theorem find the remainders obtained when
`x^(3)+(kx+8)x +k` is divided by x + 1 and x - 2.
Hence, find k if the sum of the two remainders is 1.

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To solve the problem using the Remainder Theorem, we will follow these steps: ### Step 1: Define the polynomial Let \( f(x) = x^3 + (kx + 8)x + k \). ### Step 2: Simplify the polynomial First, we can simplify \( f(x) \): \[ f(x) = x^3 + kx^2 + 8x + k \] ### Step 3: Find the remainder when divided by \( x + 1 \) Using the Remainder Theorem, the remainder when \( f(x) \) is divided by \( x + 1 \) is \( f(-1) \): \[ f(-1) = (-1)^3 + k(-1)^2 + 8(-1) + k \] Calculating this gives: \[ f(-1) = -1 + k - 8 + k = 2k - 9 \] Thus, the remainder when \( f(x) \) is divided by \( x + 1 \) is \( 2k - 9 \). ### Step 4: Find the remainder when divided by \( x - 2 \) Now, we find the remainder when \( f(x) \) is divided by \( x - 2 \), which is \( f(2) \): \[ f(2) = (2)^3 + k(2)^2 + 8(2) + k \] Calculating this gives: \[ f(2) = 8 + 4k + 16 + k = 5k + 24 \] Thus, the remainder when \( f(x) \) is divided by \( x - 2 \) is \( 5k + 24 \). ### Step 5: Set up the equation based on the problem statement According to the problem, the sum of the two remainders is 1: \[ (2k - 9) + (5k + 24) = 1 \] Simplifying this equation: \[ 2k - 9 + 5k + 24 = 1 \] \[ 7k + 15 = 1 \] \[ 7k = 1 - 15 \] \[ 7k = -14 \] \[ k = -2 \] ### Conclusion The value of \( k \) is \( -2 \). ---
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