The  functions are  and .

(a) Determination of  :

Consider .

Differentiate with respect to  on each side.

Product rule of derivatives: .

.

Substitute  in the above expression.

.

From the graph, we have  and .

 is the slope of the tangent line to the curve  at .

Slope of the tangent line to the curve  at  is the horizontal line so the slope is zero.

Thus, .

 is the slope of the tangent line to the curve  at .

Consider two points on the tangent line to the curve  at .

The two points are  and .

Slope of the tangent line .

.

Consider .

Substitute corresponding values in above expression.

(b) Determination of :

Consider .

Differentiate with respect to  on each side.

.

Quotient rule of derivatives: .

.

Substitute  in the above expression.

From the graph,  , .

 is the slope of the tangent line to the curve  at .

Consider two points on the tangent line to the curve   at .

The two points are  and .

Slope of the tangent line .

  is the slope of the tangent line to the curve  at .

Consider two points on the tangent line to the curve  at .

The two points are  and .

Slope of the tangent line .

Consider .

Substitute corresponding values in above expression.

. 

(a) 

(b) .