A relation is a function if each input x is associated with exactly one output y. For example, the equation      y = 2x + 5 defines a function because every value of x yields a unique y. However, x = y² + 1 is not a function of x, since a single x-value, such as x = 2, corresponds to two possible y-values: y = 1 and y = -1.The vertical line test helps determine whether a graph represents a function. If a vertical line intersects a curve more than once, the curve fails...

Piecewise defined functions are mathematical models where different expressions define a function over distinct intervals of the domain. These functions are useful for representing systems with varying behaviors depending on input values.For example, the function:  uses a linear rule for inputs less than or equal to –1 and a quadratic rule for values greater than –1. Although it has two formulas, it still defines a single function.Another common type is the absolute value...

Social psychology investigates how the presence and actions of others influence individual behavior, cognition, and emotion. Examining the social environment's impact provides a scientific framework for understanding how individuals perceive others and are, in turn, influenced by them. This field seeks to uncover the underlying principles guiding social interactions, exploring phenomena such as conformity, obedience, and prosocial behavior.Core Themes in Social PsychologyOne central focus of...

Psychology is the scientific discipline dedicated to understanding both observable behavior and the internal mental processes underlying such behavior. It aims to comprehend human nature and apply this understanding to solve practical problems, enhance well-being, and improve societal outcomes. An example of psychology's application is the study of prosocial behavior, such as why and under what conditions individuals might help strangers in need. This process involves describing observed...

Unlike small molecules with definite molecular weights, polymers are a mixture of individual polymer chains of varying lengths, each with a unique molecular weight.  So, the molecular weight of a polymer is expressed as an average value based on the average size of the polymer chains. The two most common forms of averages used for polymers are the number average molecular weight and weight average molecular weight.
The number average molecular weight (Mn) is the summation of the number...

Fruits form from a mature flower ovary. As seeds develop from the ovules contained within, the ovary wall undergoes a series of complex changes to form fruit. In some fruits, such as soybeans, the ovary wall dries; in other fruits, such as grapes, it remains fleshy. In some cases, organs other than the ovary contribute to fruit formation; such fruits are called accessory fruits.