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Find the domain and Range f (x)=square root x-3 divided by 6-3x ... will always be negative (because x>=3 this means 6-3x<-3) except when x=3

Squares need to be >=0. Thus
x-3>=0
Implies x must be >=3
We cannot divide by zero, thus 6-3x cannot =0.
Find where that is the case. 6=3x ->x=2

So we have x cannot be 2 and must be >=3.
We thus have the following domain in interval notation: [3,).
Since the numerator will always be positive or =0, we need only look at
the denominator and see that this will always be negative (because
x>=3 this means 6-3x<-3) except when x=3 (which gives y=0).
We thus have the follow range in interval notation: (,0]

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