Chapter 5 - Number Theory and the Real Number System - 5.6 Exponents and Scientific Notation - Exercise Set 5.6 - Page 321: 122

The zero exponent rule is defined as if \[a\] is any real number other than 0, then exponent a raised to power \[0\] is expressed as \[{{a}^{0}}=1\].

For example, consider \[a=5\] where \[5\] is greater than zero, then \[{{5}^{0}}=1\]. Hence, the zero exponent rule can be better understood with the help of the example.