Why Exponents Don't Always Add Up

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Homework Statement



Why is ##(-1)^{n+1} (-1)^{n+1} = (-1)^{2n+2}## but
##(-1)^{n+1} (1)^{n+1} = (-1)^{n+1}##
I thought in both instances you are to just add the exponents.



Homework Equations





The Attempt at a Solution


 
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1 to the power of anything is just 1. Right?

EDIT : Also, to be a bit more general, you need to have the same bases.
 
Thanks. I can't even believe myself some days
 
Jbreezy said:
Thanks. I can't even believe myself some days

Ha no problem :), we all have those.
 
Because:
I:
a^x\cdot a^x=a^{x+x}
II:
a^x\cdot b^x=(a\cdot b)^{x}
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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