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Find the length of the curve r(t) = t * e⁻t.

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Final answer:

To find the length of the curve r(t) = t * e⁻t, we can use the arc length formula. The arc length formula for a curve in parametric form is given by: As = ∫ √(r'(t)² + r(t)²) dt. In this case, the derivative of r(t) is r'(t) = (e⁻t - t * e⁻t). To calculate the integral, we can simplify the expression inside the square root and then integrate.

Step-by-step explanation:

To find the length of the curve r(t) = t * e⁻t, we can use the arc length formula. The arc length formula for a curve in parametric form is given by:

As = ∫ √(r'(t)² + r(t)²) dt

In this case, the derivative of r(t) is r'(t) = (e⁻t - t * e⁻t). To calculate the integral, we can simplify the expression inside the square root and then integrate:

√(r'(t)² + r(t)²) = √((e⁻t - t * e⁻t)² + (t * e⁻t)²)

After expanding and simplifying, we get:

√(e⁻²t + 2te⁻²t + t²e⁻²t + t²e⁻²t) = √(2te⁻²t + 2t²e⁻²t)

Finally, we can integrate this expression with respect to t to find the arc length of the curve.

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