Operation Manual

Chapter 2: Math, Angle, and Test Operations 51
Equations with Multiple Roots
Some equations have more than one solution. You can enter a new initial guess or new bounds to look
for additional solutions. Use the graph or a table of values to locate a guess as the starting value for the
solver routine.
Further Solutions
After you solve for a variable, you can continue to explore solutions from the interactive solver editor.
Edit the values of one or more variables. When you edit any variable value, the solid squares next to the
previous solution and EQ1NEQ2=diff (or leftNrt=diff) disappear. Move the cursor to the variable for
which you now want to solve and press ƒ\.
Controlling the Solution for Solver or solve(
The TI-84 Plus C solves equations through an iterative process. To control that process, enter bounds
that are relatively close to the solution and enter an initial guess within those bounds. This will help to
find a solution more quickly. Also, it will define which solution you want for equations with multiple
solutions.
Using solve( on the Home Screen or from a Program
The function solve( is available only from CATALOG or from within a program. It returns a solution
(root) of expression for variable, given an initial guess, and lower and upper bounds within which the
solution is sought. The default for
lower is L1â99. The default for upper is L1â99. solve( is valid only for
real numbers.
solve(expression,variable,guess[,{lower,upper}])
expression is assumed equal to zero. The value of variable will not be updated in memory. guess may be a
value or a list of two values. Values must be stored for every variable in expression, except variable,
before expression is evaluated. lower and upper must be entered in list format.
MATH NUM (Number) Operations
MATH NUM Menu
To display the MATH NUM menu, press ~.
MathPrint™
Classic
MATH NUM CMPLX PROB FRAC
* 1: abs(
Absolute value
2: round(
Round
3: iPart(
Integer part