Draw a graph from the following data. Draw tangents at x = 2, 4, 6 and 8. Find the slopes of these tangents. Verify that the curve drawn is y=2x2 and the slope of tangent is tan θ=dydx=4x.
x12345678910y281832507298128162200
The graph y =2x2 should be drawn by the students on a graph paper for results. To find slope at any point, draw a tangent at the point and extend the line to meet x-axis. Then, find tan θ as shown in the figure.