Chapter 8
Algebra Form and Function · 134 exercises
Problem 1
In Exercises \(1-4,\) state in words the inverse operation. Subtract 8
3 step solution
Problem 1
The graph of the function \(g(x)\) is a horizontal and/or vertical shift of the graph of \(f(x)=x^{3},\) shown in Figure \(8.19 .\) For each of the shifts described, sketch the graph of \(g(x)\) and find a formula for \(g(x)\). Shifted vertically up 3 units.
2 step solution
Problem 1
Find (a) The domain. (b) The range. $$ m(x)=9-x $$
4 step solution
Problem 1
Use substitution to compose the two functions. $$ y=u^{4} \text { and } u=x+1 $$
3 step solution
Problem 2
If we compose the two functions \(w=f(s)\) and \(q=\) \(g(w)\) using substitution, what is the input variable of the resulting function? What is the output variable?
4 step solution
Problem 2
State in words the inverse operation. Divide by 10 .
2 step solution
Problem 2
The graph of the function \(g(x)\) is a horizontal and/or vertical shift of the graph of \(f(x)=x^{3},\) shown in Figure \(8.19 .\) For each of the shifts described, sketch the graph of \(g(x)\) and find a formula for \(g(x)\). Shifted vertically down 2 units.
4 step solution
Problem 2
Find (a) The domain. (b) The range. $$ y=x^{2} $$
3 step solution
Problem 2
Use substitution to compose the two functions. $$ y=5 u^{3} \text { and } u=3-4 x $$
3 step solution
Problem 3
The graph of the function \(g(x)\) is a horizontal and/or vertical shift of the graph of \(f(x)=x^{3},\) shown in Figure \(8.19 .\) For each of the shifts described, sketch the graph of \(g(x)\) and find a formula for \(g(x)\). Shifted horizontally to the left 1 unit.
4 step solution
Problem 3
Find (a) The domain. (b) The range. $$ y=7 $$
3 step solution
Problem 3
Use substitution to compose the two functions. $$ w=r^{2}+5 \text { and } r=t^{3} $$
3 step solution
Problem 4
State in words the inverse operation. Take the ninth root.
3 step solution
Problem 4
The graph of the function \(g(x)\) is a horizontal and/or vertical shift of the graph of \(f(x)=x^{3},\) shown in Figure \(8.19 .\) For each of the shifts described, sketch the graph of \(g(x)\) and find a formula for \(g(x)\). Shifted horizontally to the right 2 units.
5 step solution
Problem 4
Find (a) The domain. (b) The range. $$ y=x^{2}-3 $$
5 step solution
Problem 4
Use substitution to compose the two functions. $$ p=2 q^{4} \text { and } D=5 p-1 $$
4 step solution
Problem 5
In Exercises \(5-8,\) find the sequence of operations to undo the sequence given. Multiply by 5 and then subtract \(2 .\)
2 step solution
Problem 5
The graph of the function \(g(x)\) is a horizontal and/or vertical shift of the graph of \(f(x)=x^{3},\) shown in Figure \(8.19 .\) For each of the shifts described, sketch the graph of \(g(x)\) and find a formula for \(g(x)\). Shifted vertically down 3 units and horizontally to the left 1 unit.
5 step solution
Problem 5
Find (a) The domain. (b) The range. $$ f(x)=x-3 $$
2 step solution
Problem 5
Use substitution to compose the two functions. $$ w=5 s^{3} \text { and } q=3+2 w $$
3 step solution
Problem 6
Find (a) The domain. (b) The range. $$ y=5 x-1 $$
4 step solution
Problem 6
Use substitution to compose the two functions. $$ P=3 q^{2}+1 \text { and } q=2 r^{3} $$
4 step solution
Problem 7
Find the sequence of operations to undo the sequence given. Raise to the \(5^{\text {th }}\) power and then multiply by 2 .
4 step solution
Problem 7
Find (a) The domain. (b) The range. $$ f(x)=\frac{1}{\sqrt{x-4}} $$
3 step solution
Problem 7
Use substitution to compose the two functions. $$ y=u^{2}+u+1 \text { and } u=x^{2} $$
3 step solution
Problem 8
Find (a) The domain. (b) The range. $$ y=\sqrt{x}+1 $$
6 step solution
Problem 8
Use substitution to compose the two functions. $$ y=2 u^{2}+5 u+7 \text { and } u=3 x^{3} $$
4 step solution
Problem 9
In Exercises \(9-12,\) show that composing the functions in either order gets us back to where we started. $$ y=7 x-5 \text { and } x=\frac{y+5}{7} $$
4 step solution
Problem 9
Find (a) The domain. (b) The range. $$ y=\sqrt{x+1} $$
3 step solution
Problem 9
Express the function as a composition of two simpler functions. $$ y=\sqrt{x^{2}+1} $$
3 step solution
Problem 10
Show that composing the functions in either order gets us back to where we started. $$ y=8 x^{3} \text { and } x=\sqrt[3]{\frac{y}{8}} $$
3 step solution
Problem 10
Find (a) The domain. (b) The range. $$ y=\frac{1}{x-2} $$
6 step solution
Problem 10
Express the function as a composition of two simpler functions. $$ y=5(x-2)^{3} $$
3 step solution
Problem 11
Show that composing the functions in either order gets us back to where we started. $$ y=x^{5}+1 \text { and } x=\sqrt[5]{y-1} $$
4 step solution
Problem 11
Find (a) The domain. (b) The range. $$ f(x)=\frac{1}{x+1}+3 $$
4 step solution
Problem 11
Express the function as a composition of two simpler functions. $$ y=3 x^{3}-2 $$
2 step solution
Problem 12
Show that composing the functions in either order gets us back to where we started. $$ y=\frac{10+x}{3} \text { and } x=3 y-10 $$
5 step solution
Problem 12
Find (a) The domain. (b) The range. $$ y=\sqrt{2 x-4} $$
2 step solution
Problem 12
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=\frac{(2 x+1)^{5}}{3} $$
4 step solution
Problem 13
In Exercises \(13-14\) (a) Write a function of \(x\) that performs the operations described. (b) Find the inverse and describe in words the sequence of operations in the inverse. Raise \(x\) to the fifth power, multiply by \(8,\) and then add \(4 .\)
3 step solution
Problem 13
Find (a) The domain. (b) The range. $$ h(z)=5+\sqrt{z-25} $$
2 step solution
Problem 13
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=\frac{17}{\left(1-x^{3}\right)^{4}} $$
4 step solution
Problem 14
The graphs are horizontal and/or vertical shifts of the graph of \(y=x^{2}\). Find a formula for each function graphed.
3 step solution
Problem 14
(a) Write a function of \(x\) that performs the operations described. (b) Find the inverse and describe in words the sequence of operations in the inverse. Subtract 5 , divide by 2 , and take the cube root.
3 step solution
Problem 14
A restaurant is open from \(2 \mathrm{pm}\) to 2 am each day, and a maximum of 200 clients can fit inside. If \(f(t)\) is the number of clients in the restaurant \(t\) hours after \(2 \mathrm{pm}\) each day, (a) What is reasonable domain for \(f ?\) (b) What is a reasonable range for \(f ?\)
3 step solution
Problem 14
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=\sqrt{5-x^{3}} $$
4 step solution
Problem 15
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=\frac{2}{\sqrt{1+\frac{1}{x}}} $$
3 step solution
Problem 15
A car's average gas mileage, \(G,\) is a function \(f(v)\) of the average speed driven, \(v\). What is a reasonable domain for \(f(v)\) ?
3 step solution
Problem 16
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=100(1+\sqrt{x})^{4} $$
3 step solution
Problem 17
In the form \(y=\) \(k \cdot(h(x))^{p}\) for some function \(h(x)\). $$ y=\left(1+x+x^{2}\right)^{3} $$
3 step solution