Question

Find (-2) for (x) = 5•3*.

Answer 1

f(-2) = 5/9

Explanation:

* lets explain the problem

∵ f(x) = 5(3)^x

- It is an exponential function

- (3) is the base of the function

- x is the exponent

- To find f(-2) means substitute x by -2

∵
`f(x)=5(3)^(x)`

∵ x = -2

∴
`f(-2)=5(3)^(-2)`

- If the power of the base is negative we can change its sign to

positive by reciprocal the base

# Ex:
`(a)^(-n)=((1)/(a))^(n)`

- Lets do that withe the base 3 and power -2

∵
`(3)^(-2)=((1)/(3))^(2)`

∴
`f(-2)=5((1)/(3))^(2)=5((1)/(9))=(5)/(9)`

* f(-2) = 5/9

Answer 2

5/9

Explanation:

F(-2)for f(x)=5•3^x

Let x = -2

f(-2)=5•3^(-2)

= 5 * 1/3^2

= 5 * 1/9

= 5/9