A number is in exponential form if it is given in the form A^b, where A is called the base and b is the power or exponent. To express a number written in exponential form in expanded form, the base number A is multiplied by itself the number of times shown by the power.

For example, if a number is given in exponent form as A^6, then this is expressed in expanded form as A x A x A x A x A x A. If A is replaced by the number 3, then the exponent is 3^6. To evaluate this exponent, multiply 3 by itself 6 times to find the answer as 729. This exponent is read as 3 raised to the 6 power. Evaluating exponents is simply repeated multiplication of the base as a factor the number of times given by the power.

When writing exponents in expanded form, it is also important to know certain rules, especially when using negative powers. For example, A^(- B) has to be expressed as 1/(A^B). To evaluate an exponent like 3^-4, it first must be expressed as 1/ 3^4, which can then be written in expanded form as 1/(3 x 3 x 3 x 3), or 1/81. It is evident that the exponential form is a more convenient and shorter way to express exponents.