186 Section 13: Finding the Roots of an Equation

Fahr's ridget falls to the ground 9.2843 seconds after he hurls it—a remarkable toss.

When No Root Is Found

You have seen how the _ key estimates and displays a root of an equation of the form f(x) = 0. However, it is possible that an equation has no real roots (that is, there is no real value of x for which the equality is true). Of course, you would not expect the calculator to find a root in this case. Instead, it displays Error 8.

Example: Consider the equation x = – 1.

which has no solution since the absolute value function is never negative. Express this equation in the required form

x + 1 = 0

and attempt to use _ to find a solution.

Keystrokes

Display

 

 

¥

000–

 

 

´b1

001–42,21, 1

a

002–

43

16

1

003–

 

1

+

004–

 

40

n

005–

43

32

G r

G

Program mode.