To know this, you first have to know what a negative exponent is. A positive exponent multiplies the base by itself a given amount of times, but a negative exponent makes a fraction with 1 in the numerator and the base and exponent in the denominator. For example:
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So let's try to do the same thing with 0 with a negative exponent.
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This is a big no-no. You can <u>never</u> have 0 as the denominator since it is undefined. Therefore, you can't raise 0 to a negative exponent.