A population of 240 birds increases at a rate of 16% annually. Jemel writes an exponential function of the form f(x) = abx to represent the number of birds after x years. Which values should she use for a and b?
Answer:
\(\boxed{\boxed{a = 240, b = 1.16}}\)
Step-by-step explanation:
General exponential function for growth or decay is,
\(y=a(1\pm r)^{x}\)
Where,
a = initial value,
r = rate of change
+ is used for growth and - is used for decay.
As here, the number of birds increasing so, the exponential function is,
\(y=a(1+r)^{x}\)
And initial value a = 240, r = rate of change = 16% = 0.16
Putting the values,
\(y=240(1+0.16)^{x}\\\\y=240(1.16)^{x}\)
Comparing this with the given equation \(y=ab^{x}\)
Hence, a = 240, b = 1.16
Answer:
The value of a is 240 and b is 1.16.
Step-by-step explanation:
Given,
The initial population of the birds = 240,
Annual rate of increasing = 16 %,
Hence, the population of birds after x years
\(P=240(1+\frac{16}{100})^x\)
\(=240(1+0.16)^x\)
\(=240(1.16)^x\)
We can put P = f(x), ( because, f(x) also shows the population of birds after x years )
\(\implies f(x) = 240(1.16)^x\) --------(1)
According to the question,
\(f(x) =ab^x\) --------(2),
From equation (1) and (2),
a = 240 and b = 1.16