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Active Calculus 2nd Ed

Activity 6.1.4.
Each of the following questions involves the arc length along a curve.
(a)
Use the definition and appropriate computational technology to determine the arc length along \(y = x^2\) from \(x = -1\) to \(x = 1\text{.}\)
(b)
Find the arc length of \(y = \sqrt{4-x^2}\) on the interval \(-2 \le x \le 2\text{.}\) Find this value in two different ways: (a) by using a definite integral, and (b) by using a familiar property of the curve.
(c)
Determine the arc length of \(y = xe^{3x}\) on the interval \([0,1]\text{.}\)
(d)
Will the integrals that arise calculating arc length typically be ones that we can evaluate exactly using the First FTC, or ones that we need to approximate? Why?
(e)
A moving particle is traveling along the curve given by \(y = f(x) = 0.1x^2 + 1\text{,}\) and does so at a constant rate of 7 cm/sec, where both \(x\) and \(y\) are measured in cm (that is, the curve \(y = f(x)\) is the path along which the object actually travels; the curve is not a “position function”). Find the position of the particle when \(t = 4\) sec, assuming that when \(t = 0\text{,}\) the particle’s location is \((0,f(0))\text{.}\)