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Find the domain of f(x) = √-6x - 7

Use two lower case o's for infinity. "oo" is how you type in infinity.

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Answer: The domain of a function is the set of all possible input values (x-values) for which the function produces a valid output (y-value).

The square root function is defined for non-negative numbers, so the expression inside the square root must be non-negative.

In this case, -6x - 7 must be greater or equal to 0.

-6x - 7 ≥ 0

x ≥ (7 + 7)/6 = 14/6 = 7/3

So the domain of the function is x ≥ 7/3, or x ∈ [7/3, ∞)

In interval notation, the domain of f(x) = √-6x - 7 is x ∈ [7/3, oo)

Explanation:

User Steven McGrath
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