Newton's Method to Estimate The Two Zeros

Question

Use​ Newton's method to estimate the two zeros of the function ​f(x)=x⁴−3x−18. Start with x₀=−1

for the​ left-hand zero and with x₀=1 for the zero on the right.​ Then, in each​ case, find x₂.

Determine x₂ when x₀= −1 and x₀= 1

Answer 1

The video shows what using x_0 = 1 is a poor choice for estimating the positive root.

x_0 = 2 works much better.

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