Taylor Series: Square root near 4:
We need to expand
with a Taylor series:
, where
is the nth derivative of f. Since this approximates the square root function best when x is close to c,
we take c = 4.0000.
For convenience we create the following table with c set to 4:
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n |
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0 |
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1 |
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2 |
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3 |
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4 |
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Taking the successive derivatives, we can fill in the middle column:
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n |
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0 |
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1 |
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2 |
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3 |
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4 |
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Now we evaluate the derivatives at 4:
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n |
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0 |
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1 |
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2 |
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3 |
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4 |
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Substitute the values from the table into the first 3 terms of the Taylor series:
![]()
![]()
which simplifies to
![]()
For
, this becomes
![]()
Evaluating this, we get ![]()