SOLUTION: Find the domain of g(x)=(sqrt)5-x

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Question 50959: Find the domain of g(x)=(sqrt)5-x
Answer by tutorcecilia(2152) About Me  (Show Source):
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[The radican (5-x) must be greater than or equal to zero because you cannot find the square root of a negative number. If the radicand is negative, it is an imaginary number.
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g(x)=(sqrt)5-x [Set 5-x>=0]
5-x>=0 [solve for x]
5>=x or x<=5 [Same value]
Than, the domain or all of the possible values for "x", must be less than or equal to 5. Try a test case. Pick the numbers 4 and 6.
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g%284%29=%28sqrt%285-4%29%29
g%284%29=%28sqrt%281%29%29 = 1 [OK]
4<=5 [This is a true statement]
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g%286%29=%28sqrt%285-6%29%29
g%286%29=%28sqrt%285-6%29%29
g%286%29=%28sqrt%28-1%29%29 [imaginary number]
So, 6<=5 is a false statement.