To model the declining population of the rhinoceros species, we can use an exponential decay function. When a population declines by a percentage each year, we can represent this decline mathematically.
- The initial population (at year \(x = 0\)) is 82 rhinoceroses.
- The population declines at a rate of 6% each year. This means that each year, 94% of the population remains (since 100% - 6% = 94%).
Thus, we can model the remaining population after \(x\) years using the equation:
\[ f(x) = P_0 \cdot (1 - r)^x \]
Where:
- \(P_0\) is the initial population (82 rhinoceroses),
- \(r\) is the rate of decline (0.06 for 6%),
- \(1 - r\) is the proportion that remains each year (0.94).
Therefore, the function becomes:
\[ f(x) = 82 \cdot (0.94)^x \]
This corresponds to option d.
So, the correct choice is:
d. f(x) = 82(0.94)^x