Variable
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Variable A quantity that can change or that may take on different values. Variable also refers to a letter or symbol representing such a quantity. Independent Variable A variable in an equation that may have its value freely chosen without considering values of any other variable. For equations such as y = 3x – 2, the independent variable is x. The variable y is not independent since it depends on the number chosen for x. Formally, an independent variable is a variable which can be assigned any permissible value without any restriction imposed by any other variable. Dependent Variable A variable that depends on one or more other variables. For equations such as y = 3x – 2, the dependent variable is y. The value of y depends on the value chosen for x. Usually the dependent variable is isolated on one side of an equation. Formally, a dependent variable is a variable in an expression , equation , or function that has its value determined by the choice of value(s) of other variable(s).
description
Variable
Transcript of Variable
VariableA quantity that can change or that may take on different values. Variable also refers to a letter or symbol representing such a quantity.Independent VariableA variable in an equation that may have its value freely chosen without considering values of any other variable. For equations such as y = 3x 2, the independent variable is x. The variable y is not independent since it depends on the number chosen for x.Formally, an independent variable is a variable which can be assigned any permissible value without any restriction imposed by any other variable.
Dependent VariableA variable that depends on one or more other variables. For equations such as y = 3x 2, the dependent variable is y. The value of y depends on the value chosen for x. Usually the dependent variable is isolated on one side of an equation. Formally, a dependent variable is a variable in an expression, equation, or function that has its value determined by the choice of value(s) of other variable(s).
ExpressionAny mathematical calculation or formula combining numbers and/or variables using sums, differences, products, quotients (including fractions), exponents, roots, logarithms, trig functions, parentheses, brackets, functions, or other mathematical operations. Expressions may not contain the equal sign (=) or any type of inequality.Examples:
Formula An expression used to calculate a desired result, such as a formula to find volume or a formula to count combinations. Formulas can also be equations involving numbers and/or variables, such as Euler's formulaEquationA mathematical sentence built from expressions using one or more equal signs (=).Examples:
RelationA set of ordered pairs.For example, {(1, 2), (3, 4), (1, a), (5, r)} is a relation. So is the set {(x, y): y = x2}; this is the set of all ordered pairs (x, y) for which y = x2.
FunctionA relation for which each element of the domain corresponds to exactly one element of the range. For example, is a function because each number x in the domain has only one possible square root. On the other hand, is not a function because there are two possible values for any positive value of x. ModelMathematical Model An equation or a system of equations representing real-world phenomena. Models also represent patterns found in graphs and/or data. Usually models are not exact matches the objects or behavior they represent. A good model should capture the essential character of whatever is being modeled.
