How do you find the domain and range ofsquare root functions?

(1) Find the domain of y = sqrt{2x + 3}

(2) Find the domain of f(x) = sqrt{2x - x^2}

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- Sep 30th 2008, 08:29 PMmagentaritaDomain of Square Root Function
How do you find the domain and range of

__square root functions?__

(1) Find the domain of y = sqrt{2x + 3}

(2) Find the domain of f(x) = sqrt{2x - x^2} - Sep 30th 2008, 09:02 PMJameson
Well since we're dealing with real numbers, we aren't allowed to take the square-root of a negative number. So find out for what x-values the expression inside the square-root is less than 0.

- Sep 30th 2008, 10:43 PMmr fantastic
- Oct 1st 2008, 04:24 PMmagentaritayes but......
- Oct 1st 2008, 05:36 PMKrizalid
Well, it's not that hard to find the "why."

Let's use our brain: having For what values of is well defined? Yes, we require that 'cause can be zero, or positive, but it can't be negative, since square roots of negative numbers don't belong to the Real numbers, that's why we require

Now, by applyin' this to your problems, you'll see this does make sense. - Oct 2nd 2008, 03:01 AMmagentaritaok