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  1. AP Pre Calculus
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What is an exponential function?

A function of the form f(x)=abxf(x) = ab^xf(x)=abx, where a is the initial value, b is the base (b > 0, b ≠ 1), and x is the exponent.

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What is an exponential function?

A function of the form f(x)=abxf(x) = ab^xf(x)=abx, where a is the initial value, b is the base (b > 0, b ≠ 1), and x is the exponent.

Define exponential growth.

Exponential growth occurs when the base b>1b > 1b>1. The function increases rapidly as x increases.

Define exponential decay.

Exponential decay occurs when 0<b<10 < b < 10<b<1. The function decreases rapidly as x increases.

What is the initial value in f(x)=abxf(x) = ab^xf(x)=abx?

The initial value is 'a', which represents the y-intercept of the function.

What is the domain of an exponential function?

The domain of an exponential function is all real numbers, (−∞,∞)(-\infty, \infty)(−∞,∞).

What is a vertical shift?

A transformation of the form g(x)=f(x)+kg(x) = f(x) + kg(x)=f(x)+k, which shifts the graph of f(x)f(x)f(x) vertically by k units.

What does concavity mean for exponential functions?

Concavity describes the curvature of the graph. Exponential functions are either always concave up or always concave down.

Define extrema in the context of exponential functions.

Extrema are maximum or minimum values of a function. Exponential functions do not have extrema on an open interval.

What is the base 'b' in exponential functions?

The base 'b' is a positive number not equal to 1 that determines whether the function represents growth or decay.

What is the significance of 'a' in f(x)=abxf(x) = ab^xf(x)=abx?

'a' represents the initial amount or starting value of the exponential function at x = 0.

What does an increasing exponential graph (b > 1) tell us?

It indicates exponential growth. The function's values increase rapidly as x increases.

What does a decreasing exponential graph (0 < b < 1) tell us?

It indicates exponential decay. The function's values decrease rapidly as x increases, approaching zero.

How does a vertical shift affect the horizontal asymptote of an exponential graph?

A vertical shift of 'k' units changes the horizontal asymptote from y = 0 to y = k.

What does the steepness of an exponential graph indicate?

The steepness indicates the rate of growth or decay. A steeper graph implies a faster rate.

What does the y-intercept of an exponential graph represent?

It represents the initial value of the function at x = 0.

How can you identify exponential growth from a graph?

The graph increases rapidly as x increases, and it is always concave up.

How can you identify exponential decay from a graph?

The graph decreases rapidly as x increases, approaching the x-axis, and it is always concave up.

What does a horizontal line on an exponential graph indicate?

A horizontal line (asymptote) indicates the limit of the function as x approaches infinity or negative infinity.

How does the base 'b' affect the shape of the exponential graph?

A larger 'b' (b > 1) results in a steeper growth curve. A smaller 'b' (0 < b < 1) results in a faster decay curve.

How to determine the vertical shift from a graph?

Compare the horizontal asymptote of the given graph with the standard exponential function's asymptote (y=0). The difference is the vertical shift.

What is the general form of an exponential function?

f(x)=abxf(x) = ab^xf(x)=abx

What is the formula for exponential growth?

f(x)=abxf(x) = ab^xf(x)=abx, where b>1b > 1b>1

What is the formula for exponential decay?

f(x)=abxf(x) = ab^xf(x)=abx, where 0<b<10 < b < 10<b<1

How do you represent a vertical shift of an exponential function?

g(x)=f(x)+kg(x) = f(x) + kg(x)=f(x)+k

What is the formula for population growth?

P(t)=P0(1+r)tP(t) = P_0(1 + r)^tP(t)=P0​(1+r)t, where P0P_0P0​ is the initial population, r is the growth rate, and t is the time.

What is the formula for compound interest?

A=P(1+rn)ntA = P(1 + \frac{r}{n})^{nt}A=P(1+nr​)nt, where A is the final amount, P is the principal, r is the interest rate, n is the number of times interest is compounded per year, and t is the number of years.

What is the formula for radioactive decay?

N(t)=N0e−λtN(t) = N_0e^{-\lambda t}N(t)=N0​e−λt, where N(t)N(t)N(t) is the amount remaining after time t, N0N_0N0​ is the initial amount, and λ\lambdaλ is the decay constant.

What is the limit of an exponential growth function as x approaches infinity?

lim⁡x→∞abx=∞\lim_{x \to \infty} ab^x = \inftylimx→∞​abx=∞ (when b > 1)

What is the limit of an exponential decay function as x approaches infinity?

lim⁡x→∞abx=0\lim_{x \to \infty} ab^x = 0limx→∞​abx=0 (when 0 < b < 1)

What is the limit of an exponential growth function as x approaches negative infinity?

lim⁡x→−∞abx=0\lim_{x \to -\infty} ab^x = 0limx→−∞​abx=0 (when b > 1)