How To Find Domain And Range?

Identify the type of relation: equation, graph, table, or set of ordered pairs

Domain (all possible input values, usually x):

If given a graph: list all x-values where the graph exists (include endpoints if filled; exclude if open)

If given a table: collect all x-values from the ordered pairs

If given ordered pairs: collect all first coordinates (x-values)

If given an equation: solve restrictions from denominators and even roots

Exclude x-values that make any denominator equal to 0

Exclude x-values that make any even root’s radicand negative

Exclude x-values that make logarithm arguments ≤ 0

Range (all possible output values, usually y):

If given a graph: list all y-values the graph attains (include endpoints if filled; exclude if open)

If given a table: collect all y-values from the ordered pairs

If given ordered pairs: collect all second coordinates (y-values)

If given an equation: solve restrictions from denominators and even roots (in terms of y when needed)

Write domain and range in correct notation:

Use interval notation: (a, b), [a, b], (a, b], [a, b)

Use unions for multiple intervals: (-∞, 3) ∪ [5, ∞)

Use set-builder notation if required: {x | condition} and {y | condition}

Suggested for You

Trending Today