4.4.3. Plot and Roots of Polynomials
The Edit → Coefficients dialogue will allow for entering coefficients for up to degree 7 polynomials. There is no need to enter the degree of the polynomial separately as the program will determine this from the field with the highest number which has a non zero value.
If a polynomial has been fitted in procedure X-Y Plots (see 126.96.36.199. Curve Fitting) just before selecting this procedure, then the estimated coefficients for this polynomial will be placed in the coefficient fields. You can then plot the same polynomial in different intervals and examine its roots.
As the program plots a polynomial within the given interval, it will also search for a change of sign in the value of the polynomial. If a change occurs then a half interval search algorithm is called to determine the value of the root. Search is stopped and the root is reported when the accuracy is better than 1E-8.