Basic Exponential Functions

Which of the following is an exponential function?

•  $y=2x+1$  

•  $y=3$  

•  $y=x^{2\ }-\ 2x-3$  

•  $y=2^x-1$  

Given the function

 $y=3^x+1$ 

What is the value of y when x = 0 ? 

• 0

• 1

• 2

• 3

Given the function

 $y\ =\ 2^{-x}$ 

What is the value of y when x = -3 ?

• 0

• 1/8

• 2

• 8

Given the function
 $y\ =\ 2^{x-1}$  

what is the value of y when x = -1?

• 0

• 1/2

• 1/4

• 1/8

Given the function $y=-2\left(3\right)^x$  

find the value of y when x = 2

• 0

• -18

• -2

• 36

What is the equation of horizontal asymptote of the function 
 $y=3^x+5\$ ?

 

• y = x

• y = 3

• y = 5

• no horizontal asymptote

What is the equation of the horizontal asymptote of 
 $y=\left(\frac{1}{2}\right)^x$  ?

• y = 0

• y = 1/2

• y = x

• no horizontal asymptote

What is the horizontal asymptote of 
 $y=1-5^x$  ?

• y = 1 

• y = -5

• y = 0

• no horizontal asymptote

Given $f\left(x\right)=2^x+3$  ,

find  $f\left(0\right)$  .

• 2

• 3

• 4

• undefined

What are the coordinates of the y-intercept of  $y=3^x-2$  ?

• (0,-1)

• (0,2)

• (0,3)

• no y-intercept