Question: what is the domain of f(x)=square root of x+1/x-2?
Answer: A square root with a negative number under the root cannot produce a real number. This means that 1−x2 must be greater than or equal to zero. Squaring a real number will always produce a positive number, so x2 must be equal to or smaller than 1 . This means x is between 0 and 1 , giving the domain of [0,1] .