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Question
Choose the correct answer for the following question.
For \[\sqrt{2} x^2 - 5x + \sqrt{2} = 0\] find the value of the discriminant.
Options
-5
17
`sqrt2`
`2sqrt2-5`
Solution
\[\sqrt{2} x^2 - 5x + \sqrt{2} = 0\]
\[a = \sqrt{2}, b = - 5, c = \sqrt{2}\]
\[\text{D} = b^2 - 4ac\]
\[ = \left( - 5 \right)^2 - 4 \times \sqrt{2} \times \sqrt{2}\]
\[ = 25 - 8\]
\[ = 17\]
Hence, the correct answer is 17.
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