Question 802467
i dont understand how we find the domain without graphing our problem is Find the range of the function for the domain {–3, 1, 4.5}. 
y = –x + 1 but i dont understand
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f(-3) = -(-3)+1 = 3 + 1 = 4
f(1) = -1+1 = 0
f(4.5) = -4.5 + 1 = -3.5
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Range:: {4,0,-3.5}
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Comment:
Finding the domain.
1st: Assume the domain is All Real Numbers.
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2nd: Look for elements of the Rule which would restrict the domain, such as::
a) even roots of a variable expression; it must be >= zero
b) a variable expression in a denominator; it cannot equal zero
c) log or ln of a variable expression; it must be >= zero
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If the Rule you have does not have a or b or c,
the domain is All Real Numbers.
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Cheers,
Stan H. 
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