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If (x - 2) is a factor of polynomial p(x...

If (x - 2) is a factor of polynomial p(x) = `x^(3) + 2x^(2) - kx + 10`, then the value of k is:

A

10

B

11

C

12

D

13

Text Solution

AI Generated Solution

The correct Answer is:
To find the value of \( k \) such that \( (x - 2) \) is a factor of the polynomial \( p(x) = x^3 + 2x^2 - kx + 10 \), we can use the Factor Theorem. According to the Factor Theorem, if \( (x - c) \) is a factor of a polynomial \( p(x) \), then \( p(c) = 0 \). ### Step-by-step Solution: 1. **Substitute \( x = 2 \) into the polynomial \( p(x) \)**: \[ p(2) = 2^3 + 2(2^2) - k(2) + 10 \] 2. **Calculate \( p(2) \)**: \[ p(2) = 8 + 2(4) - 2k + 10 \] \[ p(2) = 8 + 8 - 2k + 10 \] \[ p(2) = 26 - 2k \] 3. **Set \( p(2) \) equal to 0** (since \( (x - 2) \) is a factor): \[ 26 - 2k = 0 \] 4. **Solve for \( k \)**: \[ 2k = 26 \] \[ k = \frac{26}{2} = 13 \] ### Conclusion: The value of \( k \) is \( 13 \).
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