Proving Negative Real Numbers Using Contradiction

[zoxee]

Prove by contradiction that a real number that is less than every positive real number cannot be positive

having troubles with this

could someone give me a small hint to get started?

 

[pasmith]

Prove by contradiction that a real number that is less than every positive real number cannot be positive

having troubles with this

could someone give me a small hint to get started?

Suppose x > 0 is such that every positive real number is greater than or equal to x. What then is x/2?

 

[zoxee]

Suppose x > 0 is such that every positive real number is greater than or equal to x. What then is x/2?

I'm sorry but I can't seem to proceed even with this hint :(

 

[pasmith]

I'm sorry but I can't seem to proceed even with this hint :(

Given that x is a positive real number, is x/2 a positive real number?

 

[HallsofIvy]

I wouldn't even bother with x/2. Suppose x is positive. Can it then be "less than every positive number"

 

[berkeman]

Prove by contradiction that a real number that is less than every positive real number cannot be positive

having troubles with this

could someone give me a small hint to get started?

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