SOLUTION: state the domain of the given function f(x)=sqrt x+2

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Question 261190: state the domain of the given function
f(x)=sqrt x+2

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29+=+sqrt%28x%2B2%29
The domain of the function is the set of allowable values for x. There are several reasons for disallowing values for x:
  • Denominators must not be zero!!
  • Radicands (the expression in an radical) of even-numbered roots must never be negative (for Real-valued functions).
  • Arguments to logarithms must never be zero or negative. (IOW, they must be positive.)
  • Other undefined expressions like tan%28pi%2F2%29

The only one of these your function has is an even-numbered root. (Square roots are 2nd roots.) So the only thing we have to avoid is a negative value for the radicand. Put another way, our domain must ensure that the radicand, x+2, is equal to zero or positive. In Math terms, the domain is the solution to:
x+%2B+2+%3E=+0
Solve this and you have your domain.