# Determine whether the function represents exponential growth or exponential decay. Then graph the function. y=(0.8)^{x}

Question
Exponential growth and decay
Determine whether the function represents exponential growth or exponential decay. Then graph the function.
$$\displaystyle{y}={\left({0.8}\right)}^{{{x}}}$$

2021-01-14
Step 1
Determine weather for the following function is represent exponential growth or exponential decay. Then graph the function:
$$\displaystyle{f{{\left({x}\right)}}}={\left({0.8}\right)}^{{{x}}}$$
There is a general rule for the exponential function depending on the base of exponent as follows:
$$\displaystyle{y}={b}^{{{x}}}\ {b}\ {>}\ {1}\ \therefore\ \text{Represent for exponential growth function.}$$
$$\displaystyle{y}={b}^{{{x}}}\ {0}\ {<}\ {b}\ {<}\ {1}\ \therefore\ \text{Represent for exponential decay function.}$$</span>
For this function, $$\displaystyle\because\ {\left({0}\ {<}\ {b}\ {<}\ {1}\right)}$$</span>
$$\displaystyle\therefore$$ This function is represent for exponential decay function.
Step 2

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