Explanation
The Regula-Falsi method (also known as the False Position method) is a numerical technique for finding the roots of an equation by iteratively narrowing down the interval where the root lies. To solve the equation 3−5+3=0x3−5x+3=0, we can apply this method. Here are the steps:
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Select an interval [a,b] such that f(a) and f(b) have opposite signs, which ensures there is a root within the interval.
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Calculate the next approximation c using the formula: c=f(b)−f(a)a⋅f(b)−b⋅f(a)
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Calculate f(c).
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If ∣∣f(c)∣ is smaller than a predefined tolerance (a small positive value), consider c as the root, or if the number of iterations exceeds a maximum limit, stop.
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If f(c) and f(a) have opposite signs, update b=c; otherwise, update a=c.
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Repeat steps 2-5 until you find a satisfactory approximation for the root.
Let's start with an initial interval [][a,b], and I'll perform the first iteration:
Initial interval: []=[1,2][a,b]=[1,2]
=(1)=1−5+3=−1f(a)=f(1)=1−5+3=−1
=(2)=8−10+3=1f(b)=f(2)=8−10+3=1
So, we have opposite signs at a and b, which is good. Now, we calculate c:
=1⋅1−2⋅(−1)1−(−1)=32=1.5c=1−(−1)1⋅1−2⋅(−1)=23=1.5
Now, we calculate f(c):
(1.5)=(1.5)3−5(1.5)+3f(1.5)=(1.5)3−5(1.5)+3
You can continue the iterations, updating the interval [a,b] and calculating f(c) until ∣∣f(c)∣ is smaller than your chosen tolerance or until reach a predefined maximum number of iterations.
The Regula-Falsi method iteratively refines the approximation for the root. Be sure to apply the method for subsequent iterations to narrow down the root further.