$\"\"$

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The equation is $\"\"$ and $\"\"$ .

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Apply derivative on each side with respect to x.

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$\"\"$

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$\"\"$

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Substitute $\"\"$ in above equation. $\"\"$

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At $\"\"$ , $\"\"$

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Differentiate $\"\"$ with respect x.

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$\"\"$

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At $\"\"$ , $\"\"$

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$\"\"$

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The curvature is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in above equation.

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$\"\"$

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The curvature is $\"\"$

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$\"\"$

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Radius is $\"\"$ .

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Substitute $\"\"$ in above equation.

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$\"\"$

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The radius is $\"\"$ $\"\"$

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The curvature is $\"\"$

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The radius is $\"\"$

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