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If x+1 is a factor of the polynomial...

If `x+1` is a factor of the polynomial `2x^(2)+kx,` then the value of `k` is

A

`-3`

B

`4`

C

`2`

D

`-2`

Text Solution

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The correct Answer is:
To find the value of \( k \) such that \( x + 1 \) is a factor of the polynomial \( 2x^2 + kx \), we can follow these steps: ### Step 1: Understand the Factor Condition Since \( x + 1 \) is a factor of the polynomial, it implies that when we substitute \( x = -1 \) into the polynomial, the result should be zero. ### Step 2: Set Up the Polynomial Let \( p(x) = 2x^2 + kx \). ### Step 3: Substitute \( x = -1 \) We substitute \( x = -1 \) into the polynomial: \[ p(-1) = 2(-1)^2 + k(-1) \] ### Step 4: Simplify the Expression Calculating \( p(-1) \): \[ p(-1) = 2(1) - k = 2 - k \] ### Step 5: Set the Polynomial Equal to Zero Since \( x + 1 \) is a factor, we set \( p(-1) = 0 \): \[ 2 - k = 0 \] ### Step 6: Solve for \( k \) Now, we solve for \( k \): \[ k = 2 \] ### Conclusion Thus, the value of \( k \) is \( 2 \). ---

To find the value of \( k \) such that \( x + 1 \) is a factor of the polynomial \( 2x^2 + kx \), we can follow these steps: ### Step 1: Understand the Factor Condition Since \( x + 1 \) is a factor of the polynomial, it implies that when we substitute \( x = -1 \) into the polynomial, the result should be zero. ### Step 2: Set Up the Polynomial Let \( p(x) = 2x^2 + kx \). ...
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