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Question
If \[x = - \frac{1}{2}\],is a solution of the quadratic equation \[3 x^2 + 2kx - 3 = 0\] ,find the value of k.
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Solution
Since, \[x = - \frac{1}{2}\],is a solution of the quadratic equation \[3 x^2 + 2kx - 3 = 0\]
So, it satisfies the given equation.
\[\therefore 3 \left( - \frac{1}{2} \right)^2 + 2k\left( - \frac{1}{2} \right) - 3 = 0\]
\[ \Rightarrow \frac{3}{4} - k - 3 = 0\]
\[ \Rightarrow k = \frac{3}{4} - 3\]
\[ \Rightarrow k = \frac{3 - 12}{4}\]
\[ \Rightarrow k = - \frac{9}{4}\]
Thus, the value of k is \[- \frac{9}{4}\].
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