Problema 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
Problema 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 ?
Problema 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.
Problema 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.
Problema 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.
Problema 86
Prove the following identities.
Problema 87
Prove the following identities.
Problema 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))
Problema 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))
Problema 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))
Problema 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))
Problema 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))
Problema 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)))
Problema 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)))
Problema 89
Express in terms of using the inverse sine, inverse tangent, and inverse secant functions. <IMAGE>
Problema 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?
Problema 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.
Problema 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
Problema 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
Problema 96
Identify the amplitude and period of the following functions.
Problema 97
Identify the amplitude and period of the following functions.
Problema 98
Identify the amplitude and period of the following functions.
Problema 99
Identify the amplitude and period of the following functions.
Problema 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>
Problema 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).
Problema 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.
Problema 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 .
Problema 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.
Problema 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).
Problema 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
