$\"\"$

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The equation is $\"\"$ .

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The curve is a part of a circle.

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Formula for the arc length is $\"\"$ .

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$\"\"$ .

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Differentiate the function with respect to $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Apply the formula: $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ units.

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$\"\"$

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Check:

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Compare it circle equation $\"\"$ .

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$\"\"$ units.

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The circle with a center at the origin and radius of $\"\"$ .

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For $\"\"$ ,

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$\"\"$

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For $\"\"$ ,

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$\"\"$

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The angle formed with center as the two points is $\"\"$ , or in other words, the arc length is $\"\"$ of the circumference of the circle.

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Arc length $\"\"$ .

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$ units.

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$\"\"$

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$\"\"$ units.