Newton's Polynomial Solver
Newton's Polynomial Solver
This Demonstration shows Newton's method of finding approximate roots of an equation +b+ax=d by using three slide rules, called primary, secondary, and tertiary. We can read directly with an auxiliary primary rule. We calculate the value of polynomial +b+ax for , , and . If its value for is near , is approximately a root of the equation.
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The essence of the original construction was to use slide rules to perform multiplication, while addition was left to a person. We automated addition as well by recording values of polynomial terms and the value of the polynomial in a grid.
The current construction works for coefficients and arguments with absolute value at least 1. Suppose we want to solve the equation -6+11x=6. We enter and move sliders to get polynomial value 6 for different positions of . On the auxiliary rule we read =1, =2, =3.
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