SOLUTION: The question I have is how to determine the domain, such as in the question: State the domain in the function f(x)= 3x-6/x^2-25.

Question 194813: The question I have is how to determine the domain, such as in the question: State the domain in the function f(x)= 3x-6/x^2-25.
Found 2 solutions by edjones, solver91311:
Answer by edjones(8007) (Show Source): You can put this solution on YOUR website!
f(x)=(3x-6)/x^2-25
=(3x-6)/[(x+5)(x-5)]
The domain is all real numbers except when x=5 or -5 because division by zero is not allowed.
.
Ed
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!

The domain is that set of values for which the function is defined. You have a rational function, so you need to find any values for which the denominator would be zero. Then the domain is everything else.

Set the denominator equal to zero:

Factor the difference of two squares:

So the denominator is zero if

Hence, the domain is all real numbers except for 5 and -5. In set builder notation:

John

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