The function is .

Apply derivative on each side with respect to .

Quotient rule of derivatives : .

(a)

Slope of the tangent line to the curve is derivative of the function.

Slope of the tangent line at the point .

Point Slope form of line equation : .

Substitute  and  in point slope form.

The tangent line at the point  is .

(b)

Slope of the tangent line to the curve is derivative of the function.

Slope of the tangent line at the point .

Point Slope form of line equation : .

Substitute  and  in point slope form.

The tangent line at the point  is .

Graphs for the tangent lines  and .

The tangent lines equations are  and .

Graphs of the function .

Tangent lines equations are  and .

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