Domain Math Example 1

Follow the full solution, then compare it with the other examples linked below.

Example 1

easy
Find the domain of f(x)=xโˆ’3f(x) = \sqrt{x - 3}.

Solution

  1. 1
    The expression under a square root must be non-negative: xโˆ’3โ‰ฅ0x - 3 \geq 0.
  2. 2
    Solve: xโ‰ฅ3x \geq 3.
  3. 3
    The domain is [3,โˆž)[3, \infty).

Answer

[3,โˆž)[3, \infty)
Square root functions require non-negative radicands. Setting the expression inside the root โ‰ฅ0\geq 0 and solving gives the domain.

About Domain

The domain of a function is the complete set of allowable input values for which the function produces a defined, valid output.

Learn more about Domain โ†’

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