Proof Theory for all real numbers

AI Thread Summary
The discussion revolves around proving that if d is the maximum of two real numbers d1 and d2, and x is greater than or equal to d, then x must also be greater than or equal to both d1 and d2. The initial poster expresses confusion about how to approach the problem, suspecting a connection to logic and propositional calculus. A user clarifies that, based on the definition of maximum, it is evident that if x is greater than or equal to max(d1, d2), then it follows that x is also greater than or equal to d1 and d2. The conversation highlights the straightforward nature of the proof despite the initial uncertainty. The thread concludes with a resolution of the problem, emphasizing its mathematical basis.
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[SOLVED] Proof Theory for all real numbers

Homework Statement



If a and b are real numbers, we define max {a, b} to be the maximum of a and b or the common value if they are equal.

Prove that for all real numbers d, d1, d2, x, If d = max {d1, d2} and x ≥ d, then x ≥ d1 and x ≥ d2.

Homework Equations





The Attempt at a Solution



I do not know how to even start this problem, i have a small feeling that this exercise has something in relation with the "Logic and propositional calculus topic" but i have not find out were to link it. Any hint or good start will be appreciated.

Thanks :redface:
 
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Why in the world is this in "Engineering, Computer Science, and Technology"? Looks like a straightforward math problem to me. First, we have, from the definition, max(d_1,d_2)\ge d1 and max(d_1,d_2)\ge d2. It follows immediately that if x\ge max(d1,d2) then x\ge d1 and x\ge d2.
 
Thank you very much "HallsofIvy" i put it here since its a "Computer Science Class" at my college, I am currently studying "Computer Engineer" and i have to take this class.

Thanks!
 
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