Question

What is the value of f(x)=9^x when
x=-2

Answer 1

`f(-2) = (1)/(81)`

Explanation:

Substitute x with -2.

`f(x)=9^x`

`f(-2)=9^(-2)`

Use exponental rule (negative exponent):
`a^(-x) = (1)/(a^x)`

`f(-2) = (1)/(9^(2))`

`f(-2) = (1)/(81)`

Answer 2

1/81

Explanation:

negative exponent means its a fraction

9^-2 =

1/9^2 =

1/81