Algebra: Proving (a^2,b^2)=1 Using GCD Proof

maphec
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(a,b)=d means d is the GCD of a and b

Question:

Let (a,b)=1

Prove: (a^2,b^2)=1



The hint that we were given is to prove this by contradiction ... but, I have no idea how to go about even starting this proof ... Any and all help would be greatly appreciated!
 
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Suppose that (a,b) = 1 and that (a2,b2) = k, where k > 1 ...
 
Proof:

Supposed n is prime and that n|ab
therefore, n|a or n|b, but not both

Case 1: n|a and n does not divide b
therefore n|a^2
since n does not divide b, n does not divide b^2

Case 2: n|b and n does not divide a
therefore n|b^2
since n does not divide a, n does not divide a^2

Thus, a^2 and b^2 have no common divisors
and therefore gcd(a^2,b^2)=1
 
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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