standard_description: Explain how the unit circle in the coordinate plane enables the extension of trigonometric functions to all real numbers, interpreted as radian measures of angles traversed counterclockwise around the unit circle.
problem_activity: Task
Complete the table below. Is $\Delta x$ a constant?  If so, what constant is it? What do you notice about the 3rd column of the table?
| $x$ | $f(x)=128\cdot \left({\frac {1}{2}}\right)^x$ |               Successive quotients                |
|-----|-----------------------------------------------|---------------------------------------------------|
|  0  |                      128                      |                       ----                        |
|  1  |                      64                       | $\frac{f(1)}{f(0)}=\frac {64}{128} = \frac{1}{2}$ |
|  2  |                                               |               $\frac{f(2)}{f(1)}=$                |
|  3  |                                               |                                                   |
|  4  |                                               |                                                   |
Complete the table below. Is $\Delta x$ a constant?  If so, what constant is it? What do you notice about the 3rd column of the table?
| $x$ | $f(x)=128\cdot \left({\frac {1}{2}}\right)^x$ |                Successive quotients                 |
|-----|-----------------------------------------------|-----------------------------------------------------|
|  0  |                      128                      |                         ---                         |
|  2  |                      32                       | $\frac{f(2)}{f(0)} = \frac {32}{128} = \frac{1}{4}$ |
|  4  |                                               |                $\frac{f(4)}{f(2)}=$                 |
|  6  |                                               |                                                     |
|  8  |                                               |                                                     |
Let $f(x)=a \cdot b^x$. Let $x_0$ be any particular $x$-value. Show that if $x_0$ is increased by a constant, $\Delta x$, the successive quotient  $$\frac{f(x_0+ \Delta x)}{f(x_0)}$$ is always the same no matter what $x_0$ is.
Is b) an example of the result of c)? Explain.


aligns: no