Source: Image of frowney face, public domain, http://www.clker.com/cliparts/Q/Z/B/h/a/U/frowney-face-md.png Image of smiley face, public domain, http://www.clker.com/clipart-tango-face-smile.html Image of three indifference curves, creative commons, http://en.wikipedia.org/wiki/File:Simple-indifference-curves.svg Image of indifference curve with points by Justin Tapp
A formula used to represent consumer preferences; the utility function will result in an indifference curve mapping where each curve corresponds to a higher level of utility.
Graphical depiction of the utility function; utility increases as the mapped indifference curves move away from the origin.
Law of Diminishing Marginal Return
At some point, in either production or consumption, the economic agent will experience a decrease in the level of production or utility associated with an increase in the production or consumption of an additional unit.