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TheMindBest ResponseYou've already chosen the best response.0
D={x: where x belong to R and x >=17} R={ y>=0}
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
so, would it be 18x17>=0? and solve?
 one year ago

dpaIncBest ResponseYou've already chosen the best response.0
is this your function: \(\large f(x)=18\sqrt{x}17 \)
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
dw:1346012919057:dw
 one year ago

dpaIncBest ResponseYou've already chosen the best response.0
the domain of f is all the x values that give f(x) a real value.... so looking at the function, the function will not give you a real number when x is less than 0....
 one year ago

dpaIncBest ResponseYou've already chosen the best response.0
so the actual question in finding the domain is "what x values is \(\large \sqrt x =real\) number
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
would I do.. 18x17<0 and solve?
 one year ago

love_mathBest ResponseYou've already chosen the best response.0
root of x is always larger than 0
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
You're just looking to be sure that what's under the root does not go negative. So x cannot be negative. Since the smallest value of x is 0 (because of the domain), then the range's minimum value will happen when x is 0. (So plug in 0 for x, and see what y is). The upper limit of the function will go on forever.
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
You got it, that's the minimum of the range. As x gets bigger and bigger, there is no limit, it just grows and grows forever.
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
so.. [17,infinity) ?
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
That is your range, yes.
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
how do I find the domain with this function?
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
Well, as we talked about earlier, the domain would be anything that is a "no no". You have a square root, and here, you cannot take the square root of a negative number, as it has no real solutions.
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
anything that is NOT a "nono", sorry ;]
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
No, you simply have sqrt(x), since you cannot take the square root of a negative number, we know that x MUST be greater than or equal to 0.
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
dw:1346014535907:dw
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
We're looking for x's that might make the equation undefined. That's what it means to find the domain. The only thing in this equation that can become undefined (or have no real solutions) is the square root. Which can't be negative.
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
so x is all real numbers that are positive then?
 one year ago

qpHalcy0nBest ResponseYou've already chosen the best response.1
Yep, or in other words x >= 0
 one year ago

monroe17Best ResponseYou've already chosen the best response.0
how do I put that into interval notation though? [0,inf)
 one year ago
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