MHB Can Absolute Values of Quadratic Functions Determine Their Discriminants?

AI Thread Summary
The discussion centers on proving that if the inequality |f(x)| ≥ |g(x)| holds for all real x, then the absolute values of their discriminants satisfy |Δ_f| ≥ |Δ_g|. The quadratic functions are defined as f(x) = ax^2 + bx + c, with the discriminant Δ given by Δ = b^2 - 4ac. Participants express uncertainty about how to approach the proof, with one member referencing a challenge problem previously posted on another forum. A solution to the problem is mentioned as being available in the last post of that thread. The conversation highlights the relationship between the properties of quadratic functions and their discriminants.
Mathick
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Let $$ f(x)$$ and $$ g(x)$$ be quadratic functions such as the inequality $$ \left| f(x) \right| \ge \left| g(x) \right| $$ is hold for all real $$ x$$ . Prove that $$ \left| \Delta_f \right| \ge \left| \Delta_g \right|$$. For quadratic function $$ f(x)=ax^2+bx+c $$, then $$ \Delta=b^2-4ac. $$

I have no idea how I could start this task. Please, help!
 
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Hi Mathick,

This was actually a challenge problem that anemone posted http://mathhelpboards.com/challenge-questions-puzzles-28/prove-b-4ac-8804-b-4ac-15129.html. A solution is provided in the last post.
 
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