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What does it mean by a^b in real number system? How is it defined mathematically?
It is clear in case of exponent being an integer.
i.e., a real number a is multiplied b times where b belongs to Z
If b is a rational..say b=p/q, then a^b can be interpreted as a^(1/q) multiplied p times.
But how is it defined when b is irrational?

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marked as duplicate by T. Bongers, Daniel Fischer, anorton, ncmathsadist, leo Nov 30 '13 at 4:01

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Related. –  Cameron Buie Nov 30 '13 at 0:42
    
@Cameron Buie: thanks for the link and the answer provided in the link. –  vara Nov 30 '13 at 1:11
    
@Stefan: i tried searching before posting the question to no avail. Probably wrong choice of key words. –  vara Nov 30 '13 at 1:13
    
@vara : no problem. Glad I could help. –  Stefan Smith Nov 30 '13 at 2:08

1 Answer 1

You use the density of rationals in $\Bbb R$.Find a sequence $x_n\to \sqrt 2$ and $x_n<\sqrt 2$ for every $n$. Same for a sequence $y_n\to \sqrt 2$ with $y_n>\sqrt 2$. Then ...?

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thanks for the answer –  vara Nov 30 '13 at 1:16
    
@vara it is a little trickier than what is written here .. research it some more –  Betty Mock Nov 30 '13 at 3:15

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