Skip to main content
Ch. 2 - Functions and Graphs
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 3, Problema 61

Use the vertical line test to identify graphs in which y is a function of x.

Guida verificata passo dopo passo
1
Recall that the vertical line test is used to determine if a graph represents a function. The test states that if any vertical line drawn through the graph intersects it at more than one point, then the graph does not represent a function.
Observe the given graph, which is a parabola opening upwards. Notice the shape and how it behaves along the x-axis.
Imagine drawing vertical lines (lines parallel to the y-axis) at various x-values across the graph. For each vertical line, check how many points it intersects on the parabola.
Since the parabola opens upwards and is symmetric, each vertical line will intersect the graph at exactly one point for every x-value in the domain.
Conclude that because no vertical line intersects the graph at more than one point, the graph passes the vertical line test and therefore represents y as a function of x.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
50s

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Vertical Line Test

The vertical line test is a method to determine if a graph represents a function. If any vertical line drawn through the graph intersects it at more than one point, the graph does not represent a function. This test ensures each input (x-value) has only one output (y-value).
Video consigliato:
06:49
The Slope of a Line

Definition of a Function

A function is a relation where each input corresponds to exactly one output. In terms of graphs, this means for every x-value, there is only one y-value. This concept is fundamental to understanding why the vertical line test works.
Video consigliato:
5:57
Graphs of Common Functions

Graph of a Parabola

A parabola is a U-shaped curve that can open upwards or downwards. The graph shown is a parabola opening upwards, which typically passes the vertical line test, indicating it is a function. Recognizing common function shapes helps in quickly applying the vertical line test.
Video consigliato:
5:28
Horizontal Parabolas