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Question
If 3 is a zero of the polynomial `2x^2 + x + k`, find the value of k.
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Solution
Given: x = 3 is one zero of the polynomial `2x^2 + x + k`
Therefore, it will satisfy the above polynomial.
Now, we have
`2(3)^2 + 3 + k = 0`
`⇒ 21 + k = 0`
`⇒ k = – 21`
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