If x is odd, then 2^x + 3^x is also odd

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SUMMARY

The discussion centers on proving that if x is a positive odd integer, then the expression 2^x + 3^x is also a positive odd integer. The participant begins by expressing x in terms of an integer k, specifically as x = 2k + 1. They correctly identify that 2^x is even and 3^x is odd, leading to the conclusion that the sum of an even and an odd number results in an odd number. Thus, the statement holds true for all positive odd integers.

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Homework Statement



Prove: If x is a positive odd integer, then [tex]2^x + 3^x[/tex] is also a positive odd integer.


The Attempt at a Solution



Assume x is odd; there exists an integer k such that x = 2k + 1. Then
[tex]2^x + 3^x = 2^{2k+1} + 3^{2k+1}[/tex]

I don't know how to go about simplifying it from here.
 
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Is 2^x even or odd? What about 3^x? I'm a bit confused why they are specifying x odd. Isn't it true even if x is even?
 

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