The function is .
Linear approximation is .
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Differentiate on each side with respect to .
Find the values of and
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.
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Linear approximation at is
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Substitute and
in linear approximation equation.
The corresponding linear approximation is .
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For accuracy within 0.1.
\The middle curve is ,the upper and the lower curves are
and
.
So from the graph we can say that is accurate within 0.1 when
.
\
The corresponding linear approximation is .
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