Problem 82d
Composition of polynomials
Let ƒ be an nth-degree polynomial and let g be an mth-degree polynomial.
What is the degree of the following polynomials?
ƒ o g
Problem 82e
A culture of bacteria has a population of cells when it is first observed. The population doubles every , which means its population is governed by the function , where is the number of hours after the first observation.
How long does it take the population to reach ?
Problem 83
Symmetry Determine whether the graphs of the following equations and functions are symmetric about the x-axis, the y-axis, or the origin. Check your work by graphing.
Problem 84
Parabola properties Consider the general quadratic function ƒ(x) = ax² + bx + c , with a ≠ 0.
a. Find the coordinates of the vertex of the graph of the parabola y= ƒ(x) in terms of a, b, and c.
Problem 85
Symmetry Determine whether the graphs of the following equations and functions are symmetric about the x-axis, the y-axis, or the origin. Check your work by graphing.
Problem 86
Prove the following identities.
Problem 87
Prove the following identities.
Problem 87a
Composition of even and odd functions from graphs Assume ƒ is an even function and g is an odd function. Use the (incomplete) graphs of ƒ and g in the figure to determine the following function values. <IMAGE>
a. ƒ(g(-2))
Problem 87e
Composition of even and odd functions from graphs Assume ƒ is an even function and g is an odd function. Use the (incomplete) graphs of ƒ and g in the figure to determine the following function values. <IMAGE>
e. g(g(-7))
Problem 88a
Composition of even and odd functions from tables Assume ƒ is an even function, g is an odd function, and both are defined at 0. Use the (incomplete) table to evaluate the given compositions. <IMAGE>
a. ƒ(g(-1))
Problem 88c
Composition of even and odd functions from tables Assume ƒ is an even function, g is an odd function, and both are defined at 0. Use the (incomplete) table to evaluate the given compositions. <IMAGE>
c. ƒ(g(-3))
Problem 88e
Composition of even and odd functions from tables Assume ƒ is an even function, g is an odd function, and both are defined at 0. Use the (incomplete) table to evaluate the given compositions. <IMAGE>
e. g(g(-1))
Problem 88g
Composition of even and odd functions from tables Assume ƒ is an even function, g is an odd function, and both are defined at 0. Use the (incomplete) table to evaluate the given compositions. <IMAGE>
g. ƒ (g(g(-2)))
Problem 88i
Composition of even and odd functions from tables Assume ƒ is an even function, g is an odd function, and both are defined at 0. Use the (incomplete) table to evaluate the given compositions. <IMAGE>
i. g(g(g(-1)))
Problem 89
Express in terms of using the inverse sine, inverse tangent, and inverse secant functions. <IMAGE>
Problem 89c
{Use of Tech} Sum of squared integers Let T (n) = 1² + 2² + ... + n², where n is a positive integer. It can be shown that T (n) = n (n + 1) (2n + 1) / 8
c. What is the least value of n for which T(n) > 1000?
Problem 92a
Even and odd at the origin
a. If ƒ(0) is defined and ƒ is an even function, is it necessarily true that ƒ(0) = 0? Explain.
Problem 93
{Use of Tech} Polynomial calculations
Find a polynomial ƒ that satisfies the following properties. (Hint: Determine the degree of ƒ; then substitute a polynomial of that degree and solve for its coefficients.)
ƒ(ƒ(x)) = 9x - 8
Problem 95
{Use of Tech} Polynomial calculations
Find a polynomial ƒ that satisfies the following properties. (Hint: Determine the degree of ƒ; then substitute a polynomial of that degree and solve for its coefficients.)
ƒ(ƒ(x)) = x⁴ - 12x² + 30
Problem 96
Identify the amplitude and period of the following functions.
Problem 97
Identify the amplitude and period of the following functions.
Problem 98
Identify the amplitude and period of the following functions.
Problem 99
Identify the amplitude and period of the following functions.
Problem 103
Area of a circular sector Prove that the area of a sector of a circle of radius r associated with a central angle (measured in radians) is .
<IMAGE>
Problem 104
{Use of Tech} Triple intersection Graph the functions f(x) = x³,g(x)=3^x, and h(x)=x^x and find their common intersection point (exactly).
Problem 107
Beginning with the graphs of or , use shifting and scaling transformations to sketch the graph of the following functions. Use a graphing utility to check your work.
Problem 108
Design a sine function with the given properties.
It has a period of with a minimum value of at and a maximum value of at .
Problem 112a
Daylight function for 40 °N Verify that the function has the following properties, where t is measured in days and D is the number of hours between sunrise and sunset. It has a period of 365 days.
Problem 112b
Daylight function for 40 °N Verify that the function has the following properties, where t is measured in days and D is the number of hours between sunrise and sunset.
Its maximum and minimum values are 14.8 and 9.2, respectively, which occur approximately at and , respectively (corresponding to the solstices).
Problem 112c
Daylight function for 40 °N Verify that the function has the following properties, where t is measured in days and D is the number of hours between sunrise and sunset.
and (corresponding to the equinoxes).
Ch. 1 - Functions
