Find Where f(x) > 0: Analyzing Function Values Between x = 1 and x = 7

Question

Based on the data in the sketch, find for which X values the graph of the function f\left(x\right) > 0

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Step-by-Step Solution

To determine the values of x x at which the function f(x)>0 f(x) > 0 , we analyze the graphically provided quadratic function. The function f(x) f(x) is represented as a parabola in the given diagram. We find the points where the parabola intersects the x-axis, marking critical points for determining sign changes in the function.

Upon examining the graph, we identify the x-intercepts at x=1 x = 1 and x=7 x = 7 . The function changes sign around these x-intercepts as follows:

  • For x<1 x < 1 , the graph is above the x-axis, implying f(x)>0 f(x) > 0 .
  • For 1<x<7 1 < x < 7 , the graph is below the x-axis, implying f(x)<0 f(x) < 0 .
  • For x>7 x > 7 , the graph is again above the x-axis, implying f(x)>0 f(x) > 0 .

Consequently, the solutions where f(x)>0 f(x) > 0 are at x<1 x < 1 and x>7 x > 7 . Comparing these results with the given answer options, option 3, which is x>7 x > 7 or x<1 x < 1 , corresponds precisely to our solution.

Therefore, the correct solution to the problem is x>7 x > 7 or x<1 x < 1 .

Answer

x > 7 or x < 1