Michigan Algebra I Sept. 2012

Exponential functions are different from other functions studied in this course because the variable appears as the exponent instead of the base. In general an exponential function takes the form: y = a · b^x, where x is a real number, a ? 0, b > 0, and b ? 1. The value of a is the initial amount, or y-intercept, and b is the common ratio. It is called a common ratio because every time x is increased by a factor of one, the expression gets multiplied by the value of b.