/*! 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} Problem 2 Decide whether each function is ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Decide whether each function is one-to-one. Do not use a calculator. $$f(x)=-5 x+2$$

Short Answer

Expert verified
The function \( f(x) = -5x + 2 \) is one-to-one.

Step by step solution

01

Identify Function Type

The function given is a linear function of the form \( f(x) = mx + b \), where \( m \) is the slope and \( b \) is the y-intercept. In this case, \( m = -5 \) and \( b = 2 \). Linear functions are inherently either one-to-one or many-to-one based on their slope.
02

Analyze Slope

Observation tells us that a linear function with a non-zero slope is one-to-one. This is because the function passes the horizontal line test: every horizontal line intersects the graph at most once. Here the slope \( -5 \) is non-zero, therefore, \( f(x) = -5x + 2 \) is one-to-one.
03

Conclusion Verification

Verify the conclusion by checking that if \( f(a) = f(b) \), it implies \( a = b \). For \( f(x) = -5x + 2 \), if \( -5a + 2 = -5b + 2 \), removing the common terms results in \( a = b \), confirming the function is one-to-one.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

One-to-One Functions
A **One-to-One Function** is a type of function where each input has a unique output, and each output is associated with a single input. This means no horizontal line will touch the graph of a one-to-one function more than once.
  • To determine if a function is one-to-one, you can use the *horizontal line test*. If any horizontal line touches the graph more than once, the function is not one-to-one.
  • In the case of linear functions, such as the example given by the equation \( f(x) = -5x + 2 \), these functions are typically one-to-one if their slope \( m \) is not zero. This is because the slope determines the angle at which the line rises or falls, which affects how it interacts with horizontal lines.
Understanding one-to-one functions is key in mathematics because they ensure that each value in the range and domain map to each other precisely, which is crucial in inverse operations.
Function Analysis
**Function Analysis** involves examining the properties and characteristics of a given function to understand its behavior better.
  • To analyze a function, you first need to identify its form and components. For linear functions like \( f(x) = mx + b \), recognize the constants \( m \) (slope) and \( b \) (y-intercept).
  • The behavior of the function is largely determined by the slope \( m \). A positive slope indicates the function graph rises as it moves from left to right, while a negative slope, such as \( -5 \) in our case, means the graph falls.
  • The y-intercept \( b \) indicates where the function crosses the y-axis. For \( f(x) = -5x + 2 \), the line crosses at \( y = 2 \).
Function analysis is an essential skill as it helps predict how changing parameters alter the graph's appearance and functionality.
Slope of a Line
The **Slope of a Line** is a crucial concept in linear functions, represented by the coefficient \( m \) in the equation \( y = mx + b \). It dictates how steep the line is and the direction it goes.
  • For the equation \( f(x) = -5x + 2 \), the slope is \( -5 \). This slope tells us two things: first, the line falls as you move from left to right (a negative slope). Second, it falls steeply, as a larger absolute value implies a steeper slope.
  • The slope can be calculated using two points on the line: \((x_1, y_1)\) and \((x_2, y_2)\). The formula is: \( m = \frac{y_2-y_1}{x_2-x_1} \).
Understanding the slope of a line helps not only in determining the angle of the line but also in analyzing the relationship between variables in linear equations.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Suppose that the cost of photovoltaic cells each year after 1980 was \(75 \%\) as much as the year prior. If the cost was \(\$ 30 /\) watt in \(1980,\) model their price in dollars with an exponential function, where \(x\) corresponds to years after \(1980 .\) Then estimate the year when the price of photovoltaic cells was \(\$ 1.00\) per watt.

surface of the ocean due to rapid evaporation. In the higher latitudes, there is less evaporation, and rainfall causes the salinity to be less on the surface than at lower depths. The function given by $$ f(x)=31.5+1.1 \log (x+1) $$ models salinity to depths of 1000 meters at a latitude of \(57.5^{\circ} \mathrm{N} .\) The variable \(x\) is the depth in meters, and \(f(x)\) is in grams of salt per kilogram of seawater. (Source: Hartman, \(D\), Global Physical Climatology, Academic Press.) Approximate analytically the depth where the salinity equals 33

The interest rate stated by a financial institution is sometimes called the nominal rate. If interest is compounded, the actual rate is, in general, higher than the nominal rate, and is called the effective rate. If \(r\) is the nominal rate and \(n\) is the number of times interest is compounded annually, then $$R=\left(1+\frac{r}{n}\right)^{n}-1$$ is the effective rate. Here, \(R\) represents the annual rate that the investment would earn if simple interest were paid. Estimate the effective rate if the nominal rate is \(4.5 \%\) and interest is compounded daily \((n=365)\)

Barometric Pressure The function $$f(x)=27+1.105 \log (x+1)$$ approximates the barometric pressure in inches of mercury at a distance of x miles from the eye of a hurricane. (Source: Miller, A. and R. Anthes, Meteorology, Fifth Edition, Charles E. Merrill.) (a) Approximate the pressure 9 miles from the eye of the hurricane. (b) The ordered pair (99,29.21) belongs to this function. What information does it convey?

Tree Growth The height of a tree in feet after \(x\) years is modeled by $$f(x)=\frac{50}{1+47.5 e^{-0.22 x}}$$ (a) Make a table for \(f\) starting at \(x=10\) and incrementing by \(10 .\) What seems to be the maximum height? (b) Graph \(f\) and identify the horizontal asymptote. Explain its significance. (c) After how long was the tree 30 feet tall?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.