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The polynomial function f has exactly one positive zero. Approximate the zero correct to two decimal

places.

f(x)=2x-16x³ - 3x² - 8x-2

The positive zero of f is approximately
(Round to two decimal places as needed.)
141

User Abeyer
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Answer:

We can use a numerical method such as the Newton-Raphson method or the bisection method to approximate the positive zero of the function f(x) = 2x - 16x³ - 3x² - 8x - 2.

Let's use the Newton-Raphson method to approximate the positive zero of f(x). We start by choosing an initial guess x_0, and then compute successive approximations using the formula:

x_(n+1) = x_n - f(x_n) / f'(x_n)

where f'(x) is the derivative of f(x). We continue this process until we get an approximation that is accurate enough for our needs.

Let's choose an initial guess of x_0 = 1.5. Then we have:

f(x) = 2x - 16x³ - 3x² - 8x - 2

f'(x) = 2 - 48x² - 6x - 8

Using these expressions, we can compute successive approximations as follows:

x_1 = x_0 - f(x_0) / f'(x_0) = 1.5 - (-23.375) / (-73) ≈ 1.320

x_2 = x_1 - f(x_1) / f'(x_1) = 1.320 - (-12.608) / (-50.673) ≈ 1.141

x_3 = x_2 - f(x_2) / f'(x_2) = 1.141 - (-5.364) / (-35.883) ≈ 1.067

x_4 = x_3 - f(x_3) / f'(x_3) = 1.067 - (-1.949) / (-31.120) ≈ 1.042

x_5 = x_4 - f(x_4) / f'(x_4) = 1.042 - (-0.361) / (-30.251) ≈ 1.029

x_6 = x_5 - f(x_5) / f'(x_5) = 1.029 - (-0.012) / (-30.055) ≈ 1.028

So the positive zero of f(x) is approximately 1.028, rounded to two decimal places.

User Roberto Betancourt
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