Question 1020031
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Consider the function  f(x)=x^2+4
1. Will f(x) +4 have real zeros? Justify without any calculations. - No. {{{x^2}}} is just non-negative, and {{{x^2+4}}} has the minimum in 4 units over the zero.

2. Will f(x) -5 have real zeros? Justify without any calculations. - Yes. Its minimum is negative.

3. Will f(x-2) have real zeros? Justify without any calculations. - No. The same reason as in n.1.  Notice that f(x-2) = {{{(x-2)^2+4}}}.

4. Will f(x+4) have real zeros? Justify without any calculations. - No. The same reason as in n.1.  Notice that f(x+4) = {{{(x+4)^2+4}}}.
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