Question 673214
how do i state the domain of: g(x)= (x^2-1)/(x^2+1)
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That denominator cannot be zero.  But, no matter what value "x" takes
THAT denominator will not be zero.  
So the domain is "All Real Numbers".
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 and then: L(x)=|5-4x|
Domain is "All Real Numbers"
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Does y=4/(2x+3) define y as a function of x?
Ans: Yes, because for each value of "x" there is only one value of "y".
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Finally how do i write a cost function for this equation: 
a car rental charges $65, per day plus .45 cents per miles?
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Let Let "d" be the numberf of days ; let "m" be the number of miles.
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C(d,m) = 65d + 0.45m
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Cheers,
Stan H.
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