SOLUTION: Please help me with these I'm really lost. My teacher does not care who learns or not and keeps teaching without answering questions. 1) State the domain of the following: a

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Question 138111: Please help me with these I'm really lost. My teacher does not care who learns or not and keeps teaching without answering questions.
1) State the domain of the following:
a) g(x)=(5x)/(x^2+25)
b) f(x)=(square root of X+6)
c) K(f)=5t^2-6t+2
d) K(x)=(3x-3)/(x+2)
e) m(x)=5x-7
Answer by vleith(2983) (Show Source):
You can put this solution on YOUR website!
The domain of an expression or function is "those values of x that result in a real value for the function".
So, things like:
- a value of x that make a denonimator equal to 0
- a value of x that results in a negative square root (or a negative even root less than 1)
end up being values that are excluded from he domain.

Let's look at your questions with the above in mind.
a) g(x)=(5x)/(x^2+25)
Is there a value of x that makes ? Nope, so the domain is "all real x"
b) f(x)=(square root of X+6)
Is there a value of x that makes the
Yes, there are a bunch of them. The domain is x>= -6
c) K(f)=5t^2-6t+2
No denominator, no square root. All x
d) K(x)=(3x-3)/(x+2)
Now, you get the picture, what makes d denominator 0?
e) m(x)=5x-7
Any denominator issues? Any root issues?
Understand now?? send an email if you don't