Volume Rot. Region: Find Vol. Bounded by Curve, Y=x^2 & x=y^2, Rotated about Y=1

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SUMMARY

The volume of the solid obtained by rotating the region bounded by the curves y=x^2 and x=y^2 about the line y=1 is calculated using the washer method. The correct integral setup is pi[(1-x^2)^2 - (1-x^(1/2))^2] from x=0 to x=1. The final volume is confirmed to be 11pi/30, correcting the initial negative result due to an error in the antiderivative calculation.

PREREQUISITES
  • Understanding of the washer method for volume calculation
  • Familiarity with the curves y=x^2 and x=y^2
  • Knowledge of integral calculus and antiderivatives
  • Ability to manipulate and simplify algebraic expressions
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  • Study the washer method in detail for volume calculations
  • Practice finding volumes of solids of revolution using different curves
  • Learn about common mistakes in antiderivative calculations
  • Explore applications of volume integrals in physics and engineering
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Students studying calculus, particularly those focused on solid geometry and volume calculations, as well as educators teaching integral calculus concepts.

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Homework Statement



How do you find the volume of the solid obtained by rotating the region bounded by the given curves about the specified lines?

I keep getting a negative number and I"m becoming so frustrated! 11pi/30 is the answer in the textbook. Thank you so very much in advance!

Homework Equations



y=x^2
x=y^2
about y=1

The Attempt at a Solution



Area:
pi[(1-x^2)^2 - (1-x^(1/2))^2)]

Integral:
pi[1-2x^2+x^4-1+2x^(1/2)-x) between x=0 and x= 1

Antiderivative:
pi[(1/5x)^5-(2/3)x^3 + (2/3)x^(3/2)-(1/2)x^2]

Soln:
pi((2/10)-(5/10)) = -3pi/10??
 
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Last edited:
tree.lee said:

Homework Statement



How do you find the volume of the solid obtained by rotating the region bounded by the given curves about the specified lines?

I keep getting a negative number and I"m becoming so frustrated! 11pi/30 is the answer in the textbook. Thank you so very much in advance!

Homework Equations



y=x^2
x=y^2
about y=1

The Attempt at a Solution



Area:
pi[(1-x^2)^2 - (1-x^(1/2))^2)]

Integral:
pi[1-2x^2+x^4-1+2x^(1/2)-x) between x=0 and x= 1

Antiderivative:

pi[(1/5x)^5-(2/3)x^3 + (2/3)x^(3/2)-(1/2)x^2]
You have a mistake in the line above. The coefficient 2/3 in the third term is wrong. I get what you reported to be the correct answer.
tree.lee said:
Soln:
pi((2/10)-(5/10)) = -3pi/10??
 

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