For how many positive integers x does 2 x yield a value that ends in zero?
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2 is an even number. That is, if 2 is raised to any integer exponent, then it would yield an even numbered value. If 2 x yields a number ending in zero for some integer x , then one half of this number, i.e, 2 x − 1 , is some integer ending in 5 or 0 . But as we established earlier, if 2 is raised to any integer exponent, then it would yield an even numbered value. So 2 x can never end in 5 . If 2 x was some number ending in zero, then so would be 2 x + 1 , and every other exponent of 2 that is greater than x . Therefore, there is no integer x for which 2 x yields a number ending in zero.
If a number ends in zero, half of it can end in 5 or 0 .
2^x contains all 2's. In order to end in 0 would require the presence of a 5. Ed Gray
For a number to end in a 0 it will need at least a prime factor of 2 and 5 and as 2^{x} will never have a prime factor of 5 it will never end in 0
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If you wanted to look at the pattern, the last digit always repeats 2,4,8,6,2,4,8,6... And will never be 0