(a)

The curve is  and the point is .

Differentiate on each side with respect to .

Chain rule of derivatives : .

Slope of the tangent is derivative of the function .

Slope at of the tangent line at .

Equation of a tangent line with slope  and the point .

(b)

Graph of the function and the tangent line

(a) Equation of a tangent line .

(b) Graph of the function and the tangent line

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