Determine whether each function graphed or defined is one-to-one. y = 2(x+1)2 - 6
Table of contents
- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
3. Functions
Function Composition
Problem 40
Textbook Question
Use the definition of inverses to determine whether ƒ and g are inverses.
Verified step by step guidance1
Recall that two functions \( f \) and \( g \) are inverses if and only if \( f(g(x)) = x \) and \( g(f(x)) = x \) for all \( x \) in the domains of the compositions.
Start by finding the composition \( f(g(x)) \). Substitute \( g(x) = -\frac{1}{4}x - 2 \) into \( f(x) = -4x + 2 \), so \( f(g(x)) = -4 \left(-\frac{1}{4}x - 2\right) + 2 \).
Simplify the expression for \( f(g(x)) \) by distributing \( -4 \) and combining like terms carefully.
Next, find the composition \( g(f(x)) \). Substitute \( f(x) = -4x + 2 \) into \( g(x) = -\frac{1}{4}x - 2 \), so \( g(f(x)) = -\frac{1}{4}(-4x + 2) - 2 \).
Simplify the expression for \( g(f(x)) \) by distributing \( -\frac{1}{4} \) and combining like terms, then check if both compositions simplify to \( x \). If they do, \( f \) and \( g \) are inverses.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
2mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Definition of Inverse Functions
Two functions f and g are inverses if applying one after the other returns the original input, meaning f(g(x)) = x and g(f(x)) = x for all x in their domains. This relationship shows that each function 'undoes' the effect of the other.
Recommended video:
Graphing Logarithmic Functions
Function Composition
Function composition involves substituting one function into another, denoted as (f ∘ g)(x) = f(g(x)). To verify inverses, you compute both f(g(x)) and g(f(x)) and check if both simplify to x, confirming the inverse relationship.
Recommended video:
Function Composition
Linear Functions and Their Inverses
Linear functions have the form f(x) = mx + b, where m ≠ 0. Their inverses are also linear and can be found by solving for x in terms of y. Understanding how to manipulate and invert linear functions is essential to verify if two given linear functions are inverses.
Recommended video:
Linear Inequalities
Watch next
Master Function Composition with a bite sized video explanation from Patrick
Start learningRelated Videos
Related Practice
Textbook Question
471
views
