SOLUTION: For which value(s) of k will the roots of 4x^2 + kx + 1 = 0 be real and unequal?

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Question 175026: For which value(s) of k will the roots of 4x^2 + kx + 1 = 0 be real and unequal?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
For which value(s) of k will the roots of 4x^2 + kx + 1 = 0 be real and unequal?
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determinant = k^2 - 4*4*1 = k^2-16
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To have real and unequal roots the determinant must be > 0.
k^2-16 > 0
k^2 > 16
k > 4 or k < -4
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Cheers,
Stan H.