Chapter 4
Algebra and Trigonometry · 519 exercises
Problem 83
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log (x+4)-\log 2=\log (5 x+1) $$
5 step solution
Problem 84
Begin by graphing \(y=|x| .\) Then use this graph to obtain the graph of \(y=|x-2|+1 . \)
4 step solution
Problem 84
Let \(\log _{b} 2=A\) and \(\log _{b} 3=C .\)Write each expression in terms of \(A\) and \(C\). $$ \log _{b} 6 $$
3 step solution
Problem 84
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log (x+7)-\log 3=\log (7 x+1) $$
4 step solution
Problem 84
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \log 10^{8} $$
2 step solution
Problem 84
determine whether each statement makes sense or does not make sense, and explain your reasoning. I'm using a photocopier to reduce an image over and over by \(50 \%,\) so the exponential function \(f(x)=\left(\frac{1}{2}\right)^{x}\) models the new image size, where \(x\) is the number of reductions.
3 step solution
Problem 85
Write an equation in point-slope form and slope-intercept form of the line passing through \((1,-4)\) and parallel to the line whose equation is \(3 x-y+5=0 .\)
3 step solution
Problem 85
Let \(\log _{b} 2=A\) and \(\log _{b} 3=C .\)Write each expression in terms of \(A\) and \(C\). $$ \log _{b} 8 $$
3 step solution
Problem 85
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ 2 \log x-\log 7=\log 112 $$
3 step solution
Problem 85
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ 10^{\log 33} $$
2 step solution
Problem 85
determine whether each statement makes sense or does not make sense, and explain your reasoning. Taxing thoughts: I'm looking at data that show the number of pages in the publication that explains the U.S. tax code for selected years from 1945 thorugh 2013 . A linear function appears to be a better choice than an exponential function for modeling the number of pages in the tax code during this period.
3 step solution
Problem 86
Exercises \(86-88\) will help you prepare for the material covered in the first section of the next chapter. $$ \text { Solve: } \quad \frac{5 \pi}{4}=2 \pi x $$
4 step solution
Problem 86
Let \(\log _{b} 2=A\) and \(\log _{b} 3=C .\)Write each expression in terms of \(A\) and \(C\). $$ \log _{b} 81 $$
4 step solution
Problem 86
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log (x-2)+\log 5=\log 100 $$
3 step solution
Problem 86
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ 10^{\log 53} $$
2 step solution
Problem 86
determine whether each statement makes sense or does not make sense, and explain your reasoning. I use the natural base \(e\) when determining how much money I'd have in a bank account that earns compound interest subject to continuous compounding.
3 step solution
Problem 87
Exercises \(86-88\) will help you prepare for the material covered in the first section of the next chapter. $$ \text { Simplify: } \frac{17 \pi}{6}-2 \pi $$
3 step solution
Problem 87
Let \(\log _{b} 2=A\) and \(\log _{b} 3=C .\)Write each expression in terms of \(A\) and \(C\). $$ \log _{b} \sqrt{\frac{2}{27}} $$
3 step solution
Problem 87
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log x+\log (x+3)=\log 10 $$
5 step solution
Problem 87
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln 1 $$
2 step solution
Problem 88
Exercises \(86-88\) will help you prepare for the material covered in the first section of the next chapter. $$ \text { Simplify: }-\frac{\pi}{12}+2 \pi $$
3 step solution
Problem 88
Let \(\log _{b} 2=A\) and \(\log _{b} 3=C .\)Write each expression in terms of \(A\) and \(C\). $$ \log _{b} \sqrt{\frac{3}{16}} $$
4 step solution
Problem 88
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log (x+3)+\log (x-2)=\log 14 $$
4 step solution
Problem 88
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln e $$
2 step solution
Problem 89
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \ln (x-4)+\ln (x+1)=\ln (x-8) $$
5 step solution
Problem 89
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln e^{20} $$
2 step solution
Problem 90
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \log _{2}(x-1)-\log _{2}(x+3)=\log _{2}\left(\frac{1}{x}\right) $$
5 step solution
Problem 90
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln e^{7} $$
4 step solution
Problem 90
determine whether each statement is true or false. If the statement is false, make the necessary change(s) to produce a true statement. The functions \(f(x)=\left(\frac{1}{3}\right)^{x}\) and \(g(x)=3^{-x}\) have the same graph.
3 step solution
Problem 91
Determine whether each equation is true or false. Where possible, show work to support your conclusion. If the statement is false, make the necessary change(s) to produce a true statement. $$ \log _{4}\left(2 x^{3}\right)=3 \log _{4}(2 x) $$
3 step solution
Problem 91
Solve each logarithmic equation. Be sure to reject any value of \(x\) that is not in the domain of the original logarithmic expressions. Give the exact answer. Then, where necessary, use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution. $$ \ln (x-2)-\ln (x+3)=\ln (x-1)-\ln (x+7) $$
4 step solution
Problem 91
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln \frac{1}{e^{6}} $$
3 step solution
Problem 92
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln \frac{1}{e^{7}} $$
3 step solution
Problem 92
Graph \(f(x)=2^{x}\) and its inverse function in the same rectangular coordinate system.
5 step solution
Problem 93
Solve each equation. $$ 5^{2 x} \cdot 5^{4 x}=125 $$
5 step solution
Problem 93
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ e^{\ln 125} $$
2 step solution
Problem 93
The hyperbolic cosine and hyperbolic sine functions are defined by $$ \cosh x=\frac{e^{x}+e^{-x}}{2} \quad \text { and } \quad \sinh x=\frac{e^{x}-e^{-x}}{2} $$ a. Show that \(\cosh x\) is an even function. b. Show that \(\sinh x\) is an odd function. c. Prove that \((\cosh x)^{2}-(\sinh x)^{2}=1\)
3 step solution
Problem 94
Solve each equation. $$ 3^{x+2} \cdot 3^{x}=81 $$
4 step solution
Problem 94
Determine whether each equation is true or false. Where possible, show work to support your conclusion. If the statement is false, make the necessary change(s) to produce a true statement. $$ \ln (x+1)=\ln x+\ln 1 $$
4 step solution
Problem 94
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ e^{\ln 300} $$
2 step solution
Problem 94
Solve for \(y: 7 x+3 y=18 .\) (Section \(1.3,\) Example 7 )
3 step solution
Problem 95
Solve each equation. $$ 2|\ln x|-6=0 $$
3 step solution
Problem 95
Determine whether each equation is true or false. Where possible, show work to support your conclusion. If the statement is false, make the necessary change(s) to produce a true statement. $$ \ln (5 x)+\ln 1=\ln (5 x) $$
4 step solution
Problem 95
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln e^{9 x} $$
2 step solution
Problem 95
Find all zeros of \(f(x)=x^{3}+5 x^{2}-8 x+2 .\) (Section 3.4 Example 4 )
4 step solution
Problem 96
Solve each equation. $$ 3|\log x|-6=0 $$
3 step solution
Problem 96
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ \ln e^{13 x} $$
3 step solution
Problem 96
Solve and graph the solution set on a number line: \(2 x^{2}+5 x<12\). (Section \(3.6,\) Example 1 )
5 step solution
Problem 97
Determine whether each equation is true or false. Where possible, show work to support your conclusion. If the statement is false, make the necessary change(s) to produce a true statement. $$ \log (x+3)-\log (2 x)=\frac{\log (x+3)}{\log (2 x)} $$
3 step solution
Problem 97
In Exercises 81–100, evaluate or simplify each expression without using a calculator. $$ e^{\ln 5 x^{2}} $$
2 step solution