Finding intervals of unit length on which f(x) has it's zeros

In summary, the question is asking to find the intervals of unit length on which the given function has its zeros. The bisection method is then used to find the zeros of the function within the given intervals. The midpoints of each interval are calculated and used to find new intervals in which the roots may lie. This process continues until the desired accuracy is achieved.
  • #1
The_Iceflash
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Homework Statement


a) Find the intervals of unit length on which [tex]f(x) = 2x^{4}-8x^{3}+24x-17[/tex] has it's zeros.

b) For each of the following starting intervals, tell which of the zeros of f(x) will be found by the bisection method associated with the proof of Bolzano's THeorem. (Label the zeros x1 < x2 < x3 < x4 .)

(i) [-4,2]
(ii) [-2,4]
(iii) [0,4]

Homework Equations


N/A

The Attempt at a Solution



x|y
-2|31

-1|-31

root somewhere in [-2,-1]

x|y
0|-17

1|1

root somewhere in [0,1]

x|y
1|1

2|-1

root somewhere in [1,2]x|y
2|-1

3|1

root somewhere in [2,3][-2,-1] Midpoint = -3/2

2(-3/2)^4-8(-3/2)^3+24(-3/2)-17 = -15.875 [a1, b1] = [-3/2,1]

[0,1] Midpoint = 1/2

2(1/2)^4-8(1/2)^3+24(1/2)-17 = -5.875 [a1, b1] = [1/2,1]

[1,2] Midpoint = 3/2

2(3/2)^4-8(3/2)^3+24(3/2)-17 = 2.125 [a1, b1] = [1,3/2]

[2,3] Midpoint = 5/2

2(5/2)^4-8(5/2)^3+24(5/2)-17 = -3.875 [a1, b1] = [5/2,3]

I've gotten this far but I'm not sure where to go next. Thanks.
 
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  • #2
Please? Anyone?
 

1. How do you find intervals of unit length on which f(x) has its zeros?

To find intervals of unit length on which f(x) has its zeros, you will need to use the Intermediate Value Theorem. This theorem states that if a continuous function has different signs at two points, then there must be at least one zero between those two points. By dividing the function's domain into intervals of unit length and evaluating the function at the endpoints of each interval, you can determine where the function changes signs and therefore where its zeros are located.

2. Why is it important to find intervals of unit length for a function's zeros?

Finding intervals of unit length for a function's zeros can help us understand the behavior of the function and make predictions about its roots. It can also help us approximate the values of the zeros and identify any patterns or trends in the function's behavior.

3. What are some techniques for finding intervals of unit length for a function's zeros?

Besides using the Intermediate Value Theorem, there are other techniques that can be used to find intervals of unit length for a function's zeros. These include graphing the function, using a table of values, and using algebraic methods such as factoring or the quadratic formula.

4. Can intervals of unit length be used for any type of function?

Yes, intervals of unit length can be used for any type of function as long as the function is continuous. This means that there are no breaks or gaps in the graph of the function, and it can be drawn without lifting the pen from the paper. Most commonly, intervals of unit length are used for polynomial functions, but they can also be used for exponential, logarithmic, and trigonometric functions.

5. Are intervals of unit length always the best way to find a function's zeros?

No, intervals of unit length are not always the best way to find a function's zeros. They can be time-consuming and may not always give an accurate approximation of the zeros. In some cases, using other methods such as the Newton-Raphson method or the bisection method may be more efficient in finding the zeros of a function.

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