Texas Instruments TI-80 User Manual - Page 174

Graphing the Inverse of a Function You can use the parametric graphing feature of the TI.80 to graph the inverse relation of any function by defining the function in XãT and YãT and its inverse in XäT and YäT. Problem Procedure The function Y=.2X3ì2X+6 can be expressed in parametric form as XT=T and YT=.2T3ì2T+6. The inverse relation of the function can be expressed in parametric form as XT=F(T) and YT=T. For example, Y=.2X3ì2X+6 would be expressed as XT=.2T3ì2T+6 and YT=T. Graph the function Y=.2X3ì2X+6 and its inverse. Follow this procedure to solve the problem. 1. Select Param, CONNECTED, and Simul modes. 2. Change the Window variable values. Tmin=L10 Xmin=L15 Tmax=10 Xmax=15 Tstep=.4 Xscl=1 Ymin=L9 Ymax=9 Yscl=5 3. Enter the expressions to define the function in parametric form. X1î=T Y1î=.2Tò-2T+6 4. Enter the expressions to define the inverse in parametric form. X2î=.2Tò-2T+6 Y2î=T 11-10 Applications