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Write the formula for Newton's method and use the given initial approximation to compute the approximations x₁ and x₂

f(x)=x² −4x−5,x₀=3

User Zbee
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Final answer:

The formula for Newton's method is x_n+1 = x_n - f(x_n)/f'(x_n). To compute the approximations x₁ and x₂ for the given function f(x) = x² - 4x - 5 and initial approximation x₀ = 3, substitute the values into the formula and calculate x₁ and x₂.

Step-by-step explanation:

The formula for Newton's method is:

xn+1 = xn - f(xn)⁄f'(xn)

Now, let's use the given initial approximation x₀ = 3 to compute the approximations x₁ and x₂.

Given f(x) = x² - 4x - 5 and x₀ = 3:

  1. Calculate f(x₀) = x₀² - 4x₀ - 5
  2. Calculate f'(x₀) = 2x₀ - 4
  3. Substitute the values into the formula: x₁ = x₀ - f(x₀)⁄f'(x₀) and calculate x₁
  4. Repeat the process to compute x₂ using x₁ as the initial approximation.

User GgPeti
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