Find the tangent line approximation [tex]\( T \)[/tex] to the graph of [tex]\( f \)[/tex] at the given point. Then complete the table. (Round your answers to four decimal places.)

[tex]\[
\begin{array}{c}
f(x) = \csc(x), \quad (5, \csc 5) \\
T(x) = \csc(5) - \csc(5) \cot(5) (x - 5)
\end{array}
\][/tex]

\begin{tabular}{|c|c|c|c|c|c|}
\hline
[tex]$x$[/tex] & 4.9 & 4.99 & 5 & 5.01 & 5.1 \\
\hline
[tex]$f(x)$[/tex] & & & -1.0179 & & \\
\hline
\end{tabular}



Answer :

To find the tangent line approximation [tex]\( T(x) \)[/tex] to the graph of [tex]\( f \)[/tex] at the point [tex]\( (5, \csc 5) \)[/tex], we need to follow a few steps.

First, let's recap the formula provided for the tangent line approximation:

[tex]\[ T(x) = \csc(5) - \csc(5) \cot(5) (x - 5) \][/tex]

### Step-by-Step Solution:

1. Evaluate [tex]\( \csc(5) \)[/tex]

The cosecant function is the reciprocal of the sine function:
[tex]\[ \csc(x) = \frac{1}{\sin(x)} \][/tex]

So,
[tex]\[ \csc(5) = \frac{1}{\sin(5)} \][/tex]

Using a calculator to find the sine of 5 radians approximately, we get:
[tex]\[ \sin(5) \approx -0.958924 \][/tex]

Therefore,
[tex]\[ \csc(5) \approx \frac{1}{-0.958924} \approx -1.0429 \][/tex]

2. Evaluate [tex]\( \cot(5) \)[/tex]

The cotangent function is the reciprocal of the tangent function:
[tex]\[ \cot(x) = \frac{\cos(x)}{\sin(x)} \][/tex]

Using a calculator to find the cosine and sine of 5 radians, we get:
[tex]\[ \cos(5) \approx 0.283662 \][/tex]
[tex]\[ \sin(5) \approx -0.958924 \][/tex]

Therefore,
[tex]\[ \cot(5) \approx \frac{0.283662}{-0.958924} \approx -0.2958 \][/tex]

3. Construct the Tangent Line [tex]\( T(x) \)[/tex]

Substitute the values of [tex]\( \csc(5) \)[/tex] and [tex]\( \cot(5) \)[/tex] into the tangent line equation:

[tex]\[ T(x) = -1.0429 - (-1.0429)(-0.2958)(x - 5) \][/tex]

Simplify the equation:
[tex]\[ T(x) = -1.0429 - 0.3084(x - 5) \][/tex]

4. Calculate [tex]\( T(x) \)[/tex] for the given values of [tex]\( x \)[/tex]

Plug in the values for [tex]\( x \)[/tex] given in the table:

- For [tex]\( x = 4.9 \)[/tex]:

[tex]\[ T(4.9) = -1.0429 - 0.3084(4.9 - 5) \][/tex]
[tex]\[ T(4.9) = -1.0429 - 0.3084(-0.1) \][/tex]
[tex]\[ T(4.9) = -1.0429 + 0.0308 \][/tex]
[tex]\[ T(4.9) \approx -1.0121 \][/tex]

- For [tex]\( x = 4.99 \)[/tex]:

[tex]\[ T(4.99) = -1.0429 - 0.3084(4.99 - 5) \][/tex]
[tex]\[ T(4.99) = -1.0429 - 0.3084(-0.01) \][/tex]
[tex]\[ T(4.99) = -1.0429 + 0.0031 \][/tex]
[tex]\[ T(4.99) \approx -1.0398 \][/tex]

- For [tex]\( x = 5 \)[/tex]:

[tex]\[ T(5) = -1.0429 - 0.3084(5 - 5) \][/tex]
[tex]\[ T(5) = -1.0429 \][/tex]

- For [tex]\( x = 5.01 \)[/tex]:

[tex]\[ T(5.01) = -1.0429 - 0.3084(5.01 - 5) \][/tex]
[tex]\[ T(5.01) = -1.0429 - 0.3084(0.01) \][/tex]
[tex]\[ T(5.01) = -1.0429 - 0.0031 \][/tex]
[tex]\[ T(5.01) \approx -1.0460 \][/tex]

- For [tex]\( x = 5.1 \)[/tex]:

[tex]\[ T(5.1) = -1.0429 - 0.3084(5.1 - 5) \][/tex]
[tex]\[ T(5.1) = -1.0429 - 0.3084(0.1) \][/tex]
[tex]\[ T(5.1) = -1.0429 - 0.0308 \][/tex]
[tex]\[ T(5.1) \approx -1.0737 \][/tex]

### Complete the Table:

[tex]\[ \begin{array}{|c|c|c|c|c|c|} \hline x & 4.9 & 4.99 & 5 & 5.01 & 5.1 \\ \hline f(x) & -1.0179 & & & & \\ \hline T(x) & -1.0121 & -1.0398 & -1.0429 & -1.0460 & -1.0737 \\ \hline \end{array} \][/tex]

So, the tangent line approximation values [tex]\( T(x) \)[/tex] have been filled in as calculated above.