Chapter 12
Algebra A Combined Function · 491 exercises
Problem 27
Solve each equation. $$ \log _{4}\left(x^{2}-3 x\right)=1 $$
6 step solution
Problem 27
Write each as a logarithmic equation. $$ 5^{1 / 2}=\sqrt{5} $$
4 step solution
Problem 27
By inspection, find the value for \(x\) that makes each statement true. \(2^{x}=8\)
4 step solution
Problem 27
Find the exact value of each logarithm. $$ \log 0.0001 $$
4 step solution
Problem 27
If \(f(x)=3 x, g(x)=\sqrt{x}\), and \(h(x)=x^{2}+2,\) write each function as a composition with \(f, g\), or \(h .\) $$ F(x)=9 x^{2}+2 $$
4 step solution
Problem 27
Each of the following functions is one-to-one. Find the inverse of each function and graph the function and its inverse on the same set of axes. $$ f(x)=\frac{1}{2} x-1 $$
6 step solution
Problem 27
Solve. $$ \frac{1}{4}=2^{3 x} $$
4 step solution
Problem 27
Write each as a single logarithm. Assume that variables represent positive numbers. $$ 3 \log _{5} x+6 \log _{5} z $$
3 step solution
Problem 28
Solve each equation. $$ \log _{8}\left(x^{2}-2 x\right)=1 $$
6 step solution
Problem 28
Write each as a logarithmic equation. $$ 4^{1 / 3}=\sqrt[3]{4} $$
3 step solution
Problem 28
By inspection, find the value for \(x\) that makes each statement true. \(3^{x}=9\)
2 step solution
Problem 28
Find the exact value of each logarithm. $$ \log 0.001 $$
2 step solution
Problem 28
If \(f(x)=3 x, g(x)=\sqrt{x}\), and \(h(x)=x^{2}+2,\) write each function as a composition with \(f, g\), or \(h .\) $$ H(x)=3 x^{2}+6 $$
4 step solution
Problem 28
Each of the following functions is one-to-one. Find the inverse of each function and graph the function and its inverse on the same set of axes. $$ f(x)=-\frac{1}{2} x+2 $$
6 step solution
Problem 28
Solve. $$ \frac{1}{27}=3^{2 x} $$
3 step solution
Problem 28
Write each as a single logarithm. Assume that variables represent positive numbers. $$ 2 \log _{7} y+6 \log _{7} z $$
2 step solution
Problem 29
Solve each equation. $$ \log _{2} x+\log _{2}(3 x+1)=1 $$
5 step solution
Problem 29
Find the value of each logarithmic expression. $$ \log _{2} 8 $$
5 step solution
Problem 29
By inspection, find the value for \(x\) that makes each statement true. \(5^{x}=\frac{1}{5}\)
4 step solution
Problem 29
Find the exact value of each logarithm. $$ \ln \sqrt{e} $$
5 step solution
Problem 29
If \(f(x)=3 x, g(x)=\sqrt{x}\), and \(h(x)=x^{2}+2,\) write each function as a composition with \(f, g\), or \(h .\) $$ G(x)=3 \sqrt{x} $$
3 step solution
Problem 29
Each of the following functions is one-to-one. Find the inverse of each function and graph the function and its inverse on the same set of axes. $$ f(x)=x^{3} $$
5 step solution
Problem 29
Solve. $$ 9^{x}=27 $$
4 step solution
Problem 29
Write each as a single logarithm. Assume that variables represent positive numbers. $$ \log _{4} 2+\log _{4} 10-\log _{4} 5 $$
5 step solution
Problem 30
Solve each equation. $$ \log _{3} x+\log _{3}(x-8)=2 $$
7 step solution
Problem 30
Find the value of each logarithmic expression. $$ \log _{3} 9 $$
4 step solution
Problem 30
By inspection, find the value for \(x\) that makes each statement true. \(4^{x}=1\)
3 step solution
Problem 30
Find the exact value of each logarithm. $$ \log \sqrt{10} $$
5 step solution
Problem 30
Each of the following functions is one-to-one. Find the inverse of each function and graph the function and its inverse on the same set of axes. $$ f(x)=x^{3}-1 $$
5 step solution
Problem 30
Solve. $$ 32^{x}=4 $$
4 step solution
Problem 30
Write each as a single logarithm. Assume that variables represent positive numbers. $$ \log _{6} 21+\log _{6} 2-\log _{6} 7 $$
3 step solution
Problem 31
Solve. The size of the wolf population at Isle Royale National Park increases according to the formula \(y=y_{0} e^{0.043 t} .\) In this formula, \(t\) is time in years and \(y_{0}\) is the initial population at time 0 . If the size of the current population is 83 wolves, find how many there should be in 5 years. Round to the nearest whole number.
7 step solution
Problem 31
Find the value of each logarithmic expression. $$ \log _{2} \frac{1}{4} $$
5 step solution
Problem 31
An item is on sale for \(40 \%\) off its original price. If it is then marked down an additional \(60 \%,\) does this mean the item is free? Discuss why or why not.
4 step solution
Problem 31
Solve each equation. Give an exact solution and a four-decimal-place approximation. $$ \log x=1.3 $$
4 step solution
Problem 31
Find \(f(x)\) and \(g(x)\) so that the given function \(h(x)=(f \circ g)(x)\). $$ h(x)=(x+2)^{2} $$
4 step solution
Problem 31
Find the inverse of each one-to-one function. $$ f(x)=\frac{x-2}{5} $$
5 step solution
Problem 31
Solve. $$ 27^{x+1}=9 $$
5 step solution
Problem 31
Write each as a single logarithm. Assume that variables represent positive numbers. $$ \log _{7} 6+\log _{7} 3-\log _{7} 4 $$
3 step solution
Problem 32
Solve. The number of victims of a flu epidemic is increasing according to the formula \(y=y_{0} e^{0.075 t}\). In this formula, is time in weeks and \(y_{0}\) is the given population at time 0 . If 20,000 people are currently infected, how many might be infected in 3 weeks? Round to the nearest whole number.
7 step solution
Problem 32
Find the value of each logarithmic expression. $$ \log _{2} \frac{1}{32} $$
4 step solution
Problem 32
Uranium U-232 has a half-life of 72 years. What eventually happens to a 10 gram sample? Does it ever completely decay and disappear? Discuss why or why not.
5 step solution
Problem 32
Solve each equation. Give an exact solution and a four-decimal-place approximation. $$ \log x=2.1 $$
4 step solution
Problem 32
Find the inverse of each one-to-one function. $$ f(x)=\frac{4 x-3}{2} $$
6 step solution
Problem 32
Solve. $$ 125^{x-2}=25 $$
4 step solution
Problem 32
Find \(f(x)\) and \(g(x)\) so that the given function \(h(x)=(f \circ g)(x)\). $$ h(x)=|x-1| $$
3 step solution
Problem 32
Write each as a single logarithm. Assume that variables represent positive numbers. $$ \log _{8} 5+\log _{8} 15-\log _{8} 20 $$
5 step solution
Problem 33
Solve. The population of the Cook Islands is decreasing according to the formula \(y=y_{0} e^{-0.0277 t}\). In this formula, \(t\) is time in years and \(y_{0}\) is the initial population at time 0 . If the size of the population in 2009 was \(11,870,\) use the formula to predict the population of Cook Islands in the year \(2025 .\) Round to the nearest whole number. (Source: The World Almanac)
5 step solution
Problem 33
Find the value of each logarithmic expression. $$ \log _{25} 5 $$
5 step solution
Problem 33
Solve each equation. Give an exact solution and a four-decimal-place approximation. $$ \ln x=1.4 $$
5 step solution