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.
\![]() | \
![]() | \
![]() | \
![]() | \
![]() | \
![]() | \
![]() | \
![]() | \
31.208 | \32 | \32.808 | \40.841 | \
![]() | \
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 :
\