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Question
If `sqrt(2)` is a root of the equation `"k"x^2 + sqrt(2x) - 4` = 0, find the value of k.
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Solution
`"k"x^2 + sqrt(2x) - 4 = 0, x = sqrt(2)`
x = `sqrt(2)` is its solution
∴ `"k"(sqrt(2))^2 + sqrt(2) xx sqrt(2) - 4` = 0
⇒ 2k + 2 - 4 = 0
⇒ 2k - 2 = 0
⇒ 2k = 2
⇒ k = `(2)/(2)`
∴ k = 1
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