SOLUTION: Find the domain of the function f(x)=4/(x-9)-√(x^2-36)

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Question 1193172: Find the domain of the function f(x)=4/(x-9)-√(x^2-36)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Find the domain of the function
f%28x%29=4%2F%28x-9%29-sqrt%28x%5E2-36%29

f%28x%29=4%2F%28x-9%29-sqrt%28%28x-6%29%28x%2B6%29%29+

f%28x%29=%284-%28x+-+9%29+sqrt%28%28x-6%29%28x%2B6%29%29+%29%2F%28x+-+9%29

so, the value of x that must be excluded out of domain are: x=9, x=-6, x=6

Domain:
{ x element R : x%3C=-6 or 6%3C=x%3C9 or x%3E9 }
Interval Notation:
(-infinity,-6] ∪ [6,9) ∪ (9,infinity )