Maths - a proof question on the nature of roots of quadratic equations

AI Thread Summary
The discussion revolves around proving the inequality s² - 4s - 12 ≥ 0 for the expression s = (4x² + 3)/(2x - 1). The main challenge is understanding how to manipulate the given expression to apply the discriminant condition for real roots. Participants suggest rewriting the expression in terms of x to identify the coefficients a, b, and c for the quadratic formula. By applying the discriminant condition Δ ≥ 0, the proof can be structured effectively. The conversation emphasizes the importance of transforming the problem into a standard quadratic form to facilitate the proof process.
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I'm sorry, I just realized I put this in the wrong subsection. While I figure out how to fix that, please have a look anyway.
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Homework Statement



Given x \inℝ
And s =\frac{4(x^{2}) + 3}{2x-1}
Prove that s^{2} -4s - 12 ≥ 0

Homework Equations


The discriminant Δ, (in order for which to be real must be ≥ 0)
b^2 - 4ac ≥ 0

The Attempt at a Solution


Doing the algebra isn't the problem, I'm having trouble understanding the question itself. For this sort of proof, don't I need to work with
s =\frac{4(x^{2}) + 3}{2x-1}
instead of the statement to be proven, which is s^{2} -4s - 12 ≥ 0?

In which case, how do I apply the b^2 - 4ac rule with the linear equation part in the denominator?
 
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The variable is ##x##, so make the given equation look like a regular quadratic in ##x##. Then pick off what ##a##, ##b##, and ##c## are and write the inequality for ##\Delta## in terms of those. It will quickly resolve into what's requested.
 
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