Step 1:
\The function is
and the point is
.
Differentiate the function with respect to
.

Power rule of derivatives :
.

At the point
,
.
This is the slope of the tangent line.
\Slope of the tangent line is
.
Step 2 :
\Point-slope form of the line equation is
.
Substitute
and
in the above equation.

The tangent line equation is
.
Step 3:
\Use the linear approximation to complete the table.
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31.208 | \32 | \32.808 | \40.841 | \
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24.000 | \31.200 | \32 | \32.800 | \40.000 | \
The table compares the values of y given by linear approximation with the values of
near
.
Notice that the closer x is to 2, the better the approximation is.
\The linear approximation
depends on the point of tangency.
At the different point on the graph of
, obtain a different tangent line approximation.
The graph is :
\