A real number proof question

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In summary, the conversation discusses the rule that if a real number named "x" follows the condition n>x>=0 for every real and positive "n", then x must have the value x=0. The group also considers the possibility of x being non-zero and suggests using a proof by contradiction. The next step is to think about how to carry out this proof. One participant mentions that a positive real number n "pushes" x towards zero. This can be expressed in mathematical terms as x<0.
  • #1
transgalactic
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i got a real number called "x"

prove that if it follows this rule n>x>=0

for every real and positive "n"

then "x" must have the value x=0

??
 
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  • #2
What do you think? Consider if x is non-zero... what can you say then?
 
  • #3
if x is non zero then "n" is non zero too

what is the next step

??
 
  • #4
Office Shredder is suggesting a proof by contradiction. Your next step is to think about what you need to do to carry out this proof. This is simple enough that you shouldn't have to ask for guidance at each and every step.
 
  • #5
but from this expression
n>x>=0

"x" must not be equaled to 0

i can't see the way to solve it

??
 
  • #6
They´re telling me that a positive real number x is smaller than ANY positive real number n. So n "pushes" x to the 0.

how to say that in math
 

1. What is a real number proof question?

A real number proof question is a mathematical problem that requires the use of real numbers to prove a statement or theorem. Real numbers are numbers that can be represented on a number line and include both rational and irrational numbers.

2. How do you approach a real number proof question?

To approach a real number proof question, it is important to first understand the statement or theorem being asked to prove. Then, use logical reasoning and mathematical principles to construct a valid proof using real numbers. It may also be helpful to break the proof into smaller steps and use diagrams or examples to support your reasoning.

3. What are some common techniques used in real number proofs?

Some common techniques used in real number proofs include the use of mathematical properties such as the commutative, associative, and distributive properties, as well as the use of algebraic manipulations and logical reasoning.

4. Can you give an example of a real number proof?

Sure! One example of a real number proof is proving that the sum of two rational numbers is always rational. We can represent the two rational numbers as fractions a/b and c/d, where a, b, c, and d are integers. Then, the sum of these two fractions is (a/b)+(c/d)=(ad+bc)/bd. Since ad+bc and bd are both integers, the sum of two rational numbers is also a rational number.

5. Are there any tips for solving real number proof questions?

Yes, some tips for solving real number proof questions include starting with what you know and using that information to build towards the conclusion, breaking the proof into smaller steps, and checking your work for accuracy. It is also helpful to practice and become familiar with common techniques and properties used in real number proofs.

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