Solving the GCD of 2^10 and 10!: A Number Trick?

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large number!

1. Finding gcd(2^10,10!



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3. I attempted to try the Euclidean algorithm, but it would take forever. Is there a certain number trick?
 
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gcd(a,b) is the largest number that divides both a and b. It must be a power of 2. Why did I say that?
 
i know its a power of 2, but you still have to use the euclidean algorithm. I don't want a "guess and check process."
 
Then think of prime factors. How many 2's are there in the factorization of 10! ?
 
i got it. thanks
 
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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