Answer:
B. f(x) = 3/(x^2 +2x +1)
E. f(x) = 5/(3+x)
Step-by-step explanation:
The above functions have denominators that are zero at one point. For B, that point is x=-1; for E, that point is x=-3. When the denominator is zero, the function is undefined, so the corresponding x-value must be excluded from the domain.
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As written, choice D also qualifies. This is because the function written in the answer list here is ...
It will be undefined for x=0.
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<em>Comment on writing rational functions</em>
When the division symbol (/ or ÷) is used with a denominator that is a product or sum, that product or sum must be enclosed in parentheses. When the expression is typeset, the division bar acts as a grouping symbol. When the expression is written in text, a grouping symbol, such as parentheses, must be added.