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    Hi.
    How do you do part b? I checked the answers and it stated that x=0.1 has to be used. Why is that?

    Could someone provide me with a detailed explanation of how to obtain the answer.

    Thanks in advance.
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    Is It not 7100 = 8 - 9x then find x and substitute into the series
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    (Original post by Anfanny)
    Is It not 7100 = 8 - 9x then find x and substitute into the series
    No because that value of x is outside the interval of validity.
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    (Original post by Anfanny)
    Is It not 7100 = 8 - 9x then find x and substitute into the series
    Could you elaborate?
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    (Original post by greentron6)
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    Hi.
    How do you do part b? I checked the answers and it stated that x=0.1 has to be used. Why is that?

    Could someone provide me with a detailed explanation of how to obtain the answer.

    Thanks in advance.
    Note that the cube root of 7100 = cube root of 1000 x cube root of 7.1.

    You have to use a small value of x so that it is within the interval of validity. The expansion does not converge for large x.
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    (Original post by Mr M)
    Note that the cube root of 7100 = cube root of 1000 x cube root of 7.1.

    You have to use a small value of x so that it is within the interval of validity. The expansion does not converge for large x.
    So why don't I multiply the answer of 1.922... by 1000 at the end?
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    (Original post by greentron6)
    So why don't I multiply the answer of 1.922... by 1000 at the end?
    You need to multiply by the CUBE ROOT of 1000.
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    (Original post by Mr M)
    You need to multiply by the CUBE ROOT of 1000.
    Oh. I understand now. Thanks for your help.
 
 
 
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