contestada

Find the equation of the exponential function represented by the table below:
x y
0 2
1 1
2 0.50
3 0.25

Respuesta :

Answer:

[tex]y=2^{1-x}[/tex]

Step-by-step explanation:

Exponential Function

When we need to express the exponential relation between two variables, we use the equation

[tex]y=Cr^{x}[/tex]

where C, r are constants to be determined by using the given points from the table

For x=0, y=2, thus

[tex]2=C.r^{0}=C[/tex]

We find that C=2

The equation is now

[tex]y=2r^{x}[/tex]

Now we use the point x=1, y=1

[tex]1=2r[/tex]

We find that

[tex]\displaystyle r=\frac{1}{2}[/tex]

Thus, the equation is

[tex]\displaystyle y=2\left(\frac{1}{2}\right)^{x}[/tex]

Rearranging

[tex]y=2(2)^{-x}=2^{1-x}[/tex]

The required equation is

[tex]y=2^{1-x}[/tex]

We can easily verify the last two points are also obtained by using the equation