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Find the length of the path of c(t) = (1 + 2t, 2 + 4t) over the interval 1 ≤ t ≤ 4. Do this using:

(a) The arc length formula.

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Final answer:

To find the length of the path of c(t) = (1 + 2t, 2 + 4t) over the interval 1 ≤ t ≤ 4 using the arc length formula, we integrate the magnitude of its derivative.

Step-by-step explanation:

To find the length of the path of c(t) = (1 + 2t, 2 + 4t) over the interval 1 ≤ t ≤ 4 using the arc length formula, we need to integrate the magnitude of the derivative of c(t) with respect to t over the given interval.

The derivative of c(t) is c'(t) = (2, 4), and its magnitude is √(2^2 + 4^2) = √20 = 2√5.

Now, we integrate 2√5 with respect to t from 1 to 4:

∫14 2√5 dt = 2√5t2/2∣14 = √5(42 - 12)/2 = √5(16 - 1)/2 = √5(15)/2 = (15√5)/2

Therefore, the length of the path is (15√5)/2 units.

User Nenad Dobrilovic
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