The exponent says how many times to use the. It is used to do calculations without any calculating device. Boxed log_10 x lg x.
So your problem says that if you raise the base of 109 to the n power you would get 128 or 35714286.
A logarithm is the opposite of a power. Expressed mathematically x is the logarithm of n to the base b if bx n in which case one writes x log b n. An expression that represents repeated multiplication of the same factor is called a power. The exponent says how many times to use the.