c3 question.... Watch

Becky_666
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Report Thread starter 9 years ago
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Hey, I am stuck on this question:

Find an equation of the form ax^3 + bx + c = 0, where a, b and c are integers, which has t as a root.

For the previous part of the equation I found t= 2.877.

Thanks for any help!
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toasted-lion
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Definitely need the previous part of the question.
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Becky_666
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The sequence is defined by:

x(n+1)= cube root(31-2.5 x (n))

x1= 3

it converges at t.

i found t= 2.877
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cyborg
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How do you get an iterative formula ?

You just re-arrange the equation - so just do the reverse.

Rearrange the equation to remove the cube root.

So to start with:

x^3 = 31 - 2.5x

Rearrange this with integer coefficients of x and that's the answer.
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