HP 39GS hp 39gs_user's guide_English_E_HDPMG39AE13.pdf - Page 92

where X is distance, V0 is initial velocity, T is time, and A is acceleration. This is actually two equations, Y = X and Y = V0 T + (AT 2) / 2. Since this equation is quadratic for T, there can be both a positive and a negative solution. However, we are concerned only with positive solutions, since only positive distance makes sense. 1. Select the Solve aplet and enter the equation. Select Solve X V T A T 2 2. Find the solution for T (time) when X=30, V=2, and A=4. Enter the values for X, V, and A; then highlight the independent variable, T. 30 2 4 to highlight T 3. Use the Plot view to find an initial guess for T. First set appropriate X and Y ranges in the Plot Setup. With equation X = V x T + A x T 2 /2, the plot will produce two graphs: one for Y = X and one for X = V x T + A x T 2 /2. Since we have set X = 30 in this example, one of the graphs will be Y = 30 . Therefore, make the YRNG -5 to 35. Keep the XRNG default of - 6.5 to 6.5. SETUP-PLOT 5 35 4. Plot the graph. 7-8 Solve aplet