Find the length of the specified arc of the given curve

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SUMMARY

The length of the specified arc for the curve defined by the equation y = (1/3)√(x)(3-x) over the interval 0 ≤ x ≤ 3 is calculated using the arc length formula. The derivative f'(x) is determined to be (1/2)x^(-1/2)(1-x). Substituting this into the arc length integral results in L = ∫ from 0 to 3 of √(1 + (1/2)x^(-1/2)(1-x))^2 dx, which simplifies to L = 2^(3/2) / 3 units after evaluation. This definitive result provides the exact length of the arc.

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  • Understanding of calculus, specifically integration techniques.
  • Familiarity with the arc length formula in calculus.
  • Knowledge of derivatives and their application in finding arc lengths.
  • Ability to simplify algebraic expressions involving square roots and fractions.
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  • Study the arc length formula in detail, focusing on its derivation and applications.
  • Learn advanced integration techniques, including the power rule and substitution methods.
  • Explore the properties of derivatives, particularly in the context of curve analysis.
  • Practice solving similar problems involving arc lengths of different curves.
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Students and professionals in mathematics, particularly those studying calculus, as well as educators looking for examples of arc length calculations.

gigi9
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Calc help please!

Plz help me out w/ the problem below. Thanks.
Find the length of the specified arc of the given curve:
y=1/3sqrt(x)*(3-x), 0<=x <=3
Formular to find arc length is integral from a to b of sqrt(1+f'(x)^2)dx
I got to these steps below and not sure exactly wat to do next
***y'=1/6x^(-1/2)(3-3x)=1/2x^(-1/2)(1-x)
***V= integral from 0 to 3 of sqrt{1+[1/2x^(-1/2)*(1-x)])2} dx
=integral 0 to 3 of sqrt[1/2+1/4*x^-1+1/4*x] dx
 
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V= integral from 0 to 3 of sqrt{1+[1/2x^(-1/2)*(1-x)])2} dx
=integral 0 to 3 of sqrt[1/2+1/4*x^-1+1/4*x] dx

1/(4x) + 1/2 + x/4 can be factorized to (1/2x-1/2 + 1/21/2)2
 


To find the length of the specified arc, we can use the formula given in the problem: integral from a to b of sqrt(1+f'(x)^2)dx. In this case, a=0 and b=3, so we have:

L = integral from 0 to 3 of sqrt(1+(1/2x^(-1/2)(1-x))^2)dx

Next, we need to simplify the expression inside the square root:

1+(1/2x^(-1/2)(1-x))^2 = 1+1/4x^-1+1/4x

Substituting this into the original equation, we have:

L = integral from 0 to 3 of sqrt(1/2+1/4x^-1+1/4x) dx

Now, we can use the power rule for integration to solve this integral:

L = integral from 0 to 3 of (1/2+1/4x^-1+1/4x)^(1/2) dx

= (1/2+1/4x^-1+1/4x)^(3/2) / (3/2) from 0 to 3

= (1/2+1/4*3^-1+1/4*3)^(3/2) / (3/2) - (1/2+1/4*0^-1+1/4*0)^(3/2) / (3/2)

= (1/2+1/4+3/4)^(3/2) / (3/2) - (1/2+0+0)^(3/2) / (3/2)

= (2)^(3/2) / (3/2)

= 2^(3/2) / 3

Therefore, the length of the specified arc is 2^(3/2) / 3 units.
 

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