$\"\"$

The function $\"\"$ shown in the graph.

The point on the function $\"\"$ is $\"\"$ .

The another point passes through the function is $\"\"$ .

The slope of the function is $\"\"$ .

(a).

Find the value of $\"\"$ .

Linear approximation formula : $\"\"$ .

$\"\"$ is the slope of the function.

$\"\"$

$\"\"$ .

(b).

Find the value of $\"\"$ .

$\"\"$ .

$\"\"$

(a). $\"\"$ .

(b). $\"\"$ .