Solve for X using initial guesses of 10–8and –10–8.

Keys:

Display:

(In RPN mode)

 



X_ 

J  X 



Description:

Enters guesses.

Selects program "J" as the function. Solves for X; displays the result.

Round–Off Error

The limited (12–digit) precision of the calculator can cause errors due to rounding off, which adversely affect the iterative solutions of SOLVE and integration. For example,

[( x + 1) + 1015]2 - 1030 = 0

has no roots because f(x) is always greater than zero. However, given initial guesses of 1 and 2, SOLVE returns the answer 1.0000 due to round–off error.

Round–off error can also cause SOLVE to fail to find a root. The equation

x2 - 7 = 0

has a root at 7 . However, no 12–digit number exactly equals 7 , so the calculator can never make the function equal to zero. Furthermore, the function never changes sign SOLVE returns the message   .

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