Question

Find (-2) for (x) = 5•3*.

Answer 1

Answer:

f(-2) = 5/9

Step-by-step 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: $(a)^{-n}=(\frac{1}{a})^{n}$

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

∵ $(3)^{-2}=(\frac{1}{3})^{2}$

∴ $f(-2)=5(\frac{1}{3})^{2}=5(\frac{1}{9})=\frac{5}{9}$

* f(-2) = 5/9

Answer 2

Answer:

5/9

Step-by-step 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