A graph with an x-axis and a y-axis ranging from -6 to 6. The graph has a curve and a dashed line. The curve descends steeply from the second quadrant, reaches -0.5 on the x-axis, continues until the point 0.5 on the x-axis, and then falls sharply in the fourth quadrant, passing through a marked point at (2, -4). The dashed line starts in the first quadrant and slants downward, passes through the point (1, 2), intersects the x-axis at 1.2, and then passes through a marked point at (2, -4) in the fourth quadrant. The line is tangent to the curve at (2, -4). Using the graph of f left parenthesis x right parenthesis equals short dash 1 half x cubed, estimate the derivative of f left parenthesis x right parenthesis when x equals 2. short dash 1 over 6 6 1 over 6 short dash 6