Texas Instruments TI-89 User Manual - Page 836

LineTan CATALOG LineTan expression1, expression2 Displays the Graph screen and draws a line tangent to expression1 at the point specified. expression1 is an expression or the name of a function, where x is assumed to be the independent variable, and expression2 is the x value of the point that is tangent. Note: In the example shown, expression1 is graphed separately. LineTan does not graph expression1. In function graphing mode and a ZoomTrig window: Graph cos(x) @ " H ¥" LineTan cos(x),p/4 ¸ LineVert CATALOG LineVert x [, drawMode] Displays the Graph screen and draws, erases, or inverts a vertical line at window position x. If drawMode = 1, draws the line (default). If drawMode = 0, turns off the line. If drawMode = ë 1, turns a line that is on to off or off to on (inverts pixels along the line). Note: Regraphing erases all drawn items. See also PxlVert. In a ZoomStd window: LineVert ë 2.5 ¸ LinReg MATH/Statistics/Regressions menu LinReg list1, list2[, [list3] [, list4, list5]] Calculates the linear regression and updates all the system statistics variables. All the lists must have equal dimensions except for list5. list1 represents xlist. list2 represents ylist. list3 represents frequency. list4 represents category codes. list5 represents category include list. In function graphing mode: {0,1,2,3,4,5,6}! L1 ¸ {0,2,3,4,3,4,6}! L2 ¸ LinReg L1,L2 ¸ ShowStat ¸ {0 1 2 ...} {0 2 3 ...} Done Note: list1 through list4 must be a variable name ¸ or c1-c99 (columns in the last data variable Regeq(x)"y1(x) ¸ Done shown in the Data/Matrix Editor). list5 does not NewPlot 1,1,L1,L2 ¸ Done have to be a variable name and cannot be c1- c99. ¥% 836 Appendix A: Functions and Instructions