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) .