Question

Which could be the entire interval over which the function f(x) is positive

Answer 1

$(-\infty,-2) \cup(2,\infty)$

Explanation:

Remember you need to write complete questions in order to find exact answers. In this way you haven't provided any function, so I'll choose a quadratic function given by:

$f(x)=x^2-4x$

So we need to find the entire interval at which this function positive. Put another way:

$f(x)>0$

By using graphing tool, we get the graph shown below. As you can see:

• The function decreases from $x=-\infty \ to \ x=0$

• The function increases from $x=0 \ to \ x=\infty$
• The graph of the function is a parabola that opens up.

But what is really importan in this problem is that:

• The function is positive over the interval $(-\infty,-2) \cup(2,\infty)$

At this interval the function is positive, that is, $f(x)>0$

Learn more:

Standard equation of the graph of a parabola:

https://brainly.com/question/12896871

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