The polar equation is  and .

If the point  has Cartesian coordinates  and  polar coordinates , then  and .

Substitute in polar coordinates.

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The slope of the tangent line is derivative of the function.

Apply chain rule of derivatives : .

First find .

Consider .

Apply derivative on each side with respect to .

Apply product rule of derivatives: .

Apply formula: .

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Find .

Consider .

Apply derivative on each side with respect to .

Apply formula: .

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Substitute  and .

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The slope of the tangent line is derivative of the function at the point.

The slope of the tangent line at .

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The slope of the tangent line is .

The slope of the tangent line is .