Irrational Irrational = Irrational
Is the above equation always true for irrational numbers ? Each irrational number can be different.
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A variation on a theme....
Either x = 2 2 is rational or irrational. If it is rational then x is our counterexample. If it is irrational, then x 2 = 2 2 = 2 is our counterexample.
So while we've established that the given assertion is false we're not actually sure whether x or x 2 is a specific counterexample, (not that it matters as far as this question is concerned, but it would be interesting to know). As it turns out, by the Gelfond-Schneider theorem x is transcendental, (and hence irrational).
Note that none of integers, rational or complex numbers are closed under exponentiation. Respective counterexamples are 2 − 1 = 2 1 , 2 2 1 = 2 and i i = e − 2 π . It is closed for Z + though.
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Why are complex numbers not closed under exponentiation? Real numbers are also complex numbers with zero imaginary part.
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Good point. I guess I meant that complex numbers with non-zero imaginary components are not closed under exponentiation.
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Can you please explain why? I completely disagree.
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I'm a bit confused to be honest but it seems like you are right, as verified by wolfram alpha.
Me too. Without the parentheses, we count it from the top.
As we assume (✓2)^(✓2) to be irrational, both are right
I can't understand
e^ln(n)=n
where n is a natural number
since e is irrational so ln(n) is irrational
so the answer is false
This is wrong for n = 1 , since ln 1 = 0 is rational.
oops
i was just making an example for irrational numbers raised to irrational numbers being rational
thanks for pointing it out :)
I think it may be a little bit complicated to illustrate ln(n) is irrational emm.
When you know the e^i^pie equals -1 , you can answer this in seconds
i π is not irrational.
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Why i π is not irrational?
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Rational and irrational numbers are subsets of real numbers. i π is not a real number.
Purely imaginary number with an irrational magnitude.
can we talk about rational and irrational numbers when we have an imaginary number included?
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It's possible. Gaussian integers are complex numbers in the form a + b i where a , b are integers. I imagine you can talk about "Gaussian rationals" that are in the form a + b i where a , b are rationals. But the usual definitions of "rational number" and "irrational number" only apply for real numbers.
Well, irrational numbers have to be real
Here's a more interesting example: Let a rational non-integer y be given. Set y = x x for some real number x . It is a bit difficult to prove, but x is actually a transcendental number. This gives infinitely many counterexamples.
W ( x ) e W ( x ) = x for every x . It's also proven that W ( x ) is irrational for every algebraic number. W ( x ) is the Lambert-W function and integers is an algebraic number
What do you want to tell?????????????????????????????????????????????
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I'll give the classic example.
Assume Irrational Irrational = Irrational .
Given that 2 is irrational, then so is 2 2 .
Given that 2 2 is irrational, then so is ( 2 2 ) 2 = 2 2 = 2 .
Clearly 2 is not irrational so our original assumtion was false.