Porve Between any two real numbers lies and algebraic number
Porve \"Between any two real numbers lies and algebraic number and also a transcendental number\".
Solution
Prove:
Every interval is uncountable and R has larger cardinality then N.
Every open interval (a,b) have the same cardinality as R
All open intervals have the same cardinality.
how to prove cardinality:
if we can prove that Real Numbers and the interval (0,) have the same cardinality then we can say between any 2 real numbers lies algebraic number and transcendental number.
Consider the function f(x)=ex
The domain of this function is all real numbers.
The range of this function is from 0 to infinity.
Let ea=eb .
Then ln(ea) = ln(eb)
Then a ln(e) = b ln(e)
This means that a = b
Hence, f is injective.
Let c > 0
Then eln(c) = c
Since c > 0, ln(c) is defined, so f (ln(c)) = c
Therefore, f is surjective.
Then f is bijective.
Hence, R and (0,) have the same cardinality.
so we can say that Between any two real numbers lies and algebraic number and also a transcendental number
