Question

An exponential function f(x)=ab^x passes through the points (0,7) and (3, 189). what are the values of a and b?

Answer 1

C

Explanation:

C is the answer

Answer 2

The value of a is 7.

The value of b is 3.

Explanation:

We are given the following function:

`f(x) = ab^(x)`

Point (0,7)

This means that when
`x = 0, f(x) = 7`. So

`f(x) = ab^(x)`

`7 = ab^(0)`

`a = 7`

So

`f(x) = 7b^(x)`

(3, 189)

This means that when
`x = 3, f(x) = 189`. We use this to find b. So

`f(x) = 7b^(x)`

`189 = 7b^(3)`

`b^3 = (189)/(7)`

`b^3 = 27`

`b = \sqrt[3]{27}`

`b = 3`

The value of b is 3.