6.2 Exponential Functions

An exponential function is a function of the form where a is a positive real number (a > 0) and . The domain of f is the set of all real numbers.

(1, 6) (1, 3) (-1, 1/6) (-1, 1/3) (0, 1)

a >1 Summary of the characteristics of the graph of The domain is all real numbers. Range is set of positive numbers. No x-intercepts; y-intercept is 1. The x-axis (y=0) is a horizontal asymptote as a>1, is an increasing function and is one-to-one. The graph contains the points (0,1); (1,a), and (-1, 1/a). The graph is smooth continuous with no corners or gaps.

(-1, 6) (-1, 3) (0, 1) (1, 1/3) (1, 1/6)

0 <a <1 Summary of the characteristics of the graph of The domain is all real numbers. Range is set of positive numbers. No x-intercepts; y-intercept is 1. The x-axis (y=0) is a horizontal asymptote as 0<a<1, is a decreasing function and is one-to-one. The graph contains the points (0,1); (1,a), and (-1, 1/a). The graph is smooth continuous with no corners or gaps.

(1, 3) (0, 1)

(-1, 3) (0, 1)

(-1, 5) (0, 3) y = 2

Domain: All real numbers Range: { y | y >2 } or Horizontal Asymptote: y = 2

The number e is defined as the number that the expression In calculus this expression is expressed using limit notation as

Exponential Equations

Solve: