Inverse Functions: Definition, Formulas and Example Problems

click fraud protection

Inverse Functions: Definition, Formulas and Example Problems – What is meant by the inverse function? At this time About the knowledge.co.id will discuss about the inverse function and the things that surround it. Let's look at the discussion together in the article below to better understand it.

Inverse Functions: Definition, Formulas and Example Problems


The inverse function occurs because there is a function that is denoted by f (x) and has a relationship in each set A to each set B.

So it will be an inverse function denoted by f-1 (x) which has nothing but a relation from set B to every set A.

Thus, the inverse function is obtained from f: A → B which changes to f-1 B → A so that the origin of or the domain f (x), becomes the friendly region or the codomain becomes the result area or range f-1 (x), namely the set A. And vice versa for set B.

The inverse function or also known as the reverse function is a function that is the opposite of the original function.

A function f has an inverse function f

instagram viewer
-1 if f is a one-to-one function and a function on (bijective). This relationship can be stated as follows:

(f-1)-1 = f

Simply put, a bijective function takes place when the number of domain members is equal to the number of codomain members.

No two or more distinct domains map to the same codomain. And in each codomain has a partner in the domain. Pay attention to the pictures below:

Based on the image from the mapping above, the first mapping shows the bijective function.

The second mapping is not a bijective function because it only takes place on the on function.

Domains d and e map to members of the same codomain. The third mapping is not a bijective function because the mapping only takes place in one-to-one functions. Kodomain 9 has no partner in the member domain.

For example, f is a function that maps x to y, so we can write it as y = f (x), then f-1 is a function that maps y to x, written x = f-1(y).

For example f: A →B is a bijective function. The inverse function f is a function that combines each element of B with exactly one element of A.

The inverse function f is also represented by f-1 as follows:

There are 3 stages to determine the inverse function, among others:

  1. Change the form y = f (x) to form x = f (y).
  2. Write x as f-1(y) to f-1(y) = f(y).
  3. Replace the variable y with x so that you get the formula for the inverse function f-1(x).

In the inverse function there is a special formula like the following:


How to Find the Inverse of a Function

The way to find the inverse of a function is, for example, the function y=f (x) can be found in the following way:

  • Make changes in the equation y=f (x) to the form x=f (y).
  • Then replace x with f-1(y) so it becomes f(y) = f-1(y).
  • If you change y with x, you will find the inverse of f (x) in the form f-1.

Inverse Functions in Life

In the following, we will provide examples of inverse functions that exist in everyday life, including:

  • In the Field of Economics
    The inverse function is used in calculating as well as estimating something, for example the function of demand and supply.
  • In the Field of Chemistry
    The ivers function is used to determine the decay time of an element.
  • In the Field of Geography and Sociology
    The inverse function is achieved in optimization in industry and also population density.
  • In Physics
    The inverse function is used for quadratic function equations in explaining a motion phenomenon.

Examples of Inverse Function Problems

Problem 1

A mapping f: R→R with (g ◦ f)(x) = 2×2 + 4 x + 5 and g (x) = 2x + 3. Then f (x)=…

x2 + 2x + 1
x2 + 2x + 2
2x2 + x + 2
2x2 + 4x + 2
2x2 + 4x + 1

Answer:

Define f(x)

(g ◦ f)(x) = 2×2 + 4x + 5
g (f(x)) = 2×2 + 4x + 5
2(f (x)) + 3 = 2×2 + 4x + 5
f(x) = x2 + 2x + 1

The answer: A

  • Question 2

If g (x – 2) = 2x – 3 and (f ◦ g)(x – 2) = 4×2 – 8x + 3, then f(-3) =…

-3
0
3
12
15

Answer:

g(x – 2) = 2x – 3
(f ◦ g)(x – 2) = 4×2 – 8x + 3
f (g(x – 2)) = 4×2 – 8x + 3
f (2x – 3) = 4×2 – 8x + 3

Define f(-3)
If -3 = 2x – 3 then x = 0
So that:
f(-3) = 4(0)2 – 8(0) + 3 = 3

The answer: A

Problem 3.

Let f: R→ R and g: R→R, f (x) = x + 2 and (g ◦ f)(x) = 2×2 + 4x – 6, Also suppose that x1and x2 are roots of g ( x) = 0 then x1 + 2×2 =…

0
1
3
4
5

Answer:

Define g(x).

(g ◦ f)(x) = 2×2 + 4x – 6
g (f(x)) = 2×2 + 4x – 6
g(x+2) = 2×2 + 4x -6
g (x) = 2(x – 2)2 + 4(x – 2) – 6 = 2×2 – 8x + 8 + 4x – 8 – 6 = 2×2 – 4x – 6

Define x1 + 2×2

g(x) = 0
2×2 – 4x – 6 = 0
x2 – 2x – 3 = 0
(x-3)(x+1) = 0
x1=3 →x2 = -1, so 3
x1 = 2×2 = 3+2 (-1) = 1

or

x1 = -1 → x2 = 3, so
x1 + 2×2 = (-1) + 2(3) = 5

The answer: E

Inverse Functions: Definition, Formulas and Example Problems
  • Problem 4

Find the inverse of the function F(x) = (2x + 2)2 – 5 ?

the usual way
Let F(x) = y
y = (2x + 2)2 – 5
y + 5 = (2x + 2)2
(y + 5)1/2 = 2x + 2
(y + 5)1/2 – 2 = 2x
[(y +5)1/2 – 2]/2 = x

Then f-1(x) = [(x + 5)1/2 – 2]/2

Alternative way
operation x on the function F(x) = (2x + 2)2 – 5 :

Multiply by 2
Plus 2
Squared
Minus 5

do it in reverse and in the following order:

Plus 5
A rank 2 root
Minus 2
divided by 2

The inverse result is f-1(x) = [(x + 5)1/2 – 2]/2

Thus the review from About the knowledge.co.id about Inverse Function, hopefully can add to your insight and knowledge. Thank you for visiting and don't forget to read other articles

List of contents

Recommendation:

  • Mathematical Induction: Principles, Proof of Series, Divisibility,… Mathematical Induction: Principles, Proof of Series, Divisibility, Equations and Example Problems - What is Mathematical Induction ?On this occasion, Seputarknowledge.co.id will discuss about Baseball and other things covers it.…
  • Cone formulas, characteristics, properties, elements and examples of problems Cone Formulas, Characteristics, Properties, Elements and Examples Problem - How to calculate the area and volume of a shape cone space?, On this occasion, Seputarknowledge.co.id will discuss it and of course about other things Which…
  • Examples of Scientific Work: Functions and Rules of Language Examples of Scientific Papers: Functions and Rules of Language - What are examples of good and correct forms of writing scientific papers? Previously, Seputar the knowledge.co.id has discussed Scientific Work: Definition, Characteristics, Benefits,…
  • Definition of White Blood Cells (Leukocytes), Functions, Types and… Definition of White Blood Cells (Leukocytes), Functions, Types and Characteristics - This time we will discuss about blood. Blood is an important thing for humans, if you've ever heard that someone is...
  • The Constitution Is: Definition, Function, Purpose, Type, Space… Constitution Is: Definition, Function, Purpose, Type, Scope and History - What is meant by a constitution? On this occasion, Seputarknowledge.co.id will discuss what is the constitution and what surrounds it.…
  • Mangrove Forests Are: Characteristics, Benefits, Causes of Damage And… Mangrove Forests Are: Characteristics, Benefits, Triggers of Damage and Countermeasures - What is meant by forest mangroves and their functions? On this occasion, Se regarding the knowledge.co.id will discuss it and of course about it other…
  • Business Entity: Definition, Form, Type and Comparison Business Entity: Definition, Form, Type and Comparison - What is meant by a Business Entity? This time around the knowledge.co.id will discuss the Business Entity and the things that surround it. Let's see together…
  • √ Definition of Sets and Examples of Set Statistical Problems… Definition of Sets and Examples of Set Statistical Questions (Complete) - Before knowing how to set examples of statistical questions. The following is the definition of the set. Sets are the basic concept of all branches of mathematics. Father…
  • The Collapse of the Kediri Kingdom: History and Legacy The Fall of the Kediri Kingdom: History and Legacy - The Kediri Kingdom or the Kadiri Kingdom or the Panjalu Kingdom was a kingdom that existed in East Java between 1042-1222. The kingdom is in the city…
  • Fractional Numbers: Definition and Types Fractional Numbers: Definition and Types - Here we will discuss one of the subjects that is said to be difficult. The subject is mathematics, for some people say so. In math...
  • Crafts from Hard Materials: Definition, Types, Techniques,… Crafts from Hard Materials: Definition, Types, Techniques, Stages of How to Make and Examples - What is it handicrafts made of hard materials? On this occasion, Seputarknowledge.co.id will discuss it and of course things…
  • News Text: Definition, Characteristics, Elements, Structure, Terms,… News Text: Definition, Characteristics, Elements, Structure, Terms, Language Rules, Writing Guidelines and Examples - What is meant by News Text? On this occasion, Seputarknowledge.co.id will discuss about...
  • Example of historical story text in Indonesia Examples of historical story texts in Indonesia – What are examples of historical stories like? This time around the knowledge.co.id will discuss examples of historical stories and their structures. Let's take a look at the discussion in the article on…
  • Pencak Silat: Definition, History, Characteristics, Purpose, Techniques,… Pencak Silat: Definition, History, Characteristics, Purpose, Techniques, and Levels - Does anyone know what it is Pencak Silat? On this occasion, Seputarknowledge.co.id will discuss Pencak Silat and other things other…
  • Optical Instruments: Definition, Functions, Types and Parts Optical Instruments: Definition, Functions, Types and Parts - What are optical devices and what are their types? On this occasion, Seputarknowledge.co.id will discuss it and of course other things that...
  • Cartesian Coordinates: Definition, System, Diagram and Examples… Cartesian Coordinates: Definition, Systems, Diagrams and Example Problems - What do you mean by Cartesian coordinates ?On this occasion, Seputarknowledge.co.id will discuss Cartesian coordinates and other things covers it.…
  • Sample Physical Education Questions for Class 11 (XI) SMA/MA/SMK Semester 1 and 2 Examples of Physical Education Questions for Class 11 (XI) for SMA/MA/SMK Semester 1 and 2 (2019 and 2020) - On this occasion, Seputarknowledge.co.id will discuss examples of Physical Education Questions for Class 11 Multiple Choice and Essay...
  • Dynamic Fluids: Types, Features, Bernoulli Equation, Theorems… Dynamic Fluids: Types, Properties, Bernoulli's Equation, Toricelli's Theorem, Formulas And Examples of Problems - What is it dynamic fluids and their types? about…
  • Types of Cats: Race and Color Differences Types of Cats: Race and Color Differences - Do you know what types of cats are? On this occasion, Seputarknowledge.co.id will discuss this and of course other things as well covered it. Let us…
  • Sharia Accounting: Understanding According to Experts, Basic… Syari'ah Accounting: Understanding According to Experts, Legal Basis, Characteristics, Purpose, Principles, Characteristics And The advantages - What is sharia accounting and its advantages? discuss it and...
  • Protected Forest: Definition, Function, Legal Basis for Protecting… Protected Forest: Definition, Function, Legal Basis for Protection and Examples - What is meant by protected forest? On this occasion, Seputarknowledge.co.id will discuss it and of course other things Also…
  • Communism Is: Definition, History, Characteristics, Figures and Impacts… Communism Is: Definition, History, Characteristics, Figures and Impacts of Communism - What is meant by Communism and Communism? On this occasion, Seputarknowledge.co.id will discuss whether it is communism or communism…
  • Papers: Definition, Characteristics, Functions, Types, Structures, Methods… Papers: Definition, Characteristics, Functions, Types, Structure, How to Make and Examples - What is meant by Papers and how to write them properly and correctly? On this occasion Seputarknowledge.co.id will…
  • Renaissance Age Renaissance Period: Definition, History, Background and Characters - What is meant by the Renaissance era? On this occasion, Seputarknowledge.co.id will discuss it and of course about other things that also…
  • The formula for calculating the surface area of ​​a tube without a lid Formula for calculating the surface area of ​​a tube without a lid - How to calculate the surface area of ​​a tube without a lid close?, On this occasion Seputarknowledge.co.id will discuss it and of course other formulas as well covered it. Let us…
  • Integers are: Definition and Kinds Integers are: Understanding and Kinds - For most people mathematics is one subjects they don't like, because according to them mathematics makes them dizzy and difficult with formulas And…
  • Permutations: Definition, Formulas and Example Problems Permutation: Definition, Formulas and Example Problems - What is permutation and how to calculate it the math? On this occasion, Seputarknowledge.co.id will discuss permutations and other things about it. Let's see…
  • Linguistic Elements of Explanatory Text: Characteristics, Structure, Types,… Linguistic Elements of Explanatory Text: Definition, Characteristics, Structure, Types and Examples - What is explanatory text with its linguistic elements? On this occasion, Seputarknowledge.co.id will discuss what is explanatory text and element…
  • Respiratory Plant Plants: Definition, Types, Process… Respiratory Organs of Plants: Definition, Types, Respiration Process and Relationship of Respiration with Photosynthesis – Anything and how does the process of breathing plants? Of course…
  • Examples of Satire Poetry Examples of Satire Poetry - What does satire poetry mean and examples? Let's look at the discussion together in the article on…
insta story viewer