Chapter 4: Problem 100
Solve each equation. Find the exact solutions. $$\log _{x}(9)=\frac{1}{2}$$
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 4: Problem 100
Solve each equation. Find the exact solutions. $$\log _{x}(9)=\frac{1}{2}$$
These are the key concepts you need to understand to accurately answer the question.
All the tools & learning materials you need for study success - in one app.
Get started for free
Visual Magnitude of a Star If all stars were at the same distance, it would be a simple matter to compare their brightness. However, the brightness that we see, the apparent visual magnitude \(m,\) depends on a star's intrinsic brightness, or absolute visual magnitude \(M_{V},\) and the distance \(d\) from the observer in parsecs ( 1 parsec \(=3.262\) light years), according to the formula \(m=M_{V}-5+5 \cdot \log (d) .\) The values of \(M_{V}\) range from \(-8\) for the intrinsically brightest stars to \(+15\) for the intrinsically faintest stars. The nearest star to the sun, Alpha Centauri, has an apparent visual magnitude of 0 and an absolute visual magnitude of 4.39 . Find the distance \(d\) in parsecs to Alpha Centauri.
Use the following definition. In chemistry, the \(\mathrm{pH}\) of a solution is defined to be $$\mathrm{pH}=-\log \left[H^{+}\right],$$ where \(H^{+}\) is the hydrogen ion concentration of the solution in moles per liter. Distilled water has a pH of approximately 7. A substance with a pH under 7 is called an acid, and one with a pH over 7 is called a base. The gastric juices in your stomach have a hydrogen ion concentration of \(10^{-1}\) moles per liter. Find the pH of your gastric juices.
Noise Pollution The level of a sound in decibels (db) is determined by the formula $$\text { sound level }=10 \cdot \log \left(I \times 10^{12}\right) \mathrm{db}$$ where \(I\) is the intensity of the sound in watts per square meter. To combat noise pollution, a city has an ordinance prohibiting sounds above 90 db on a city street. What value of \(I\) gives a sound of 90 db?
Marginal Revenue The revenue in dollars from the sale of \(x\) items is given by the function \(R(x)=500 \cdot \log (x+1) .\) The marginal revenue function \(M R(x)\) is the difference quotient for \(R(x)\) when \(h=1 .\) Find \(M R(x)\) and write it as a single logarithm. What happens to the marginal revenue as \(x\) gets larger and larger?
Economic Impact An economist estimates that \(75 \%\) of the money spent in Chattanooga is respent in four days on the average in Chattanooga. So if \(P\) dollars are spent, then the economic impact \(I\) in dollars after \(n\) respendings is given by $$I=P(0.75)^{n}$$ When \(I <0.02 P,\) then \(P\) no longer has an impact on the economy. If the Telephone Psychics Convention brings \(\$ 1.3\) million to the city, then in how many days will that money no longer have an impact on the city?
What do you think about this solution?
We value your feedback to improve our textbook solutions.